John Snow: A Legacy of Disease Detectives

Snow cholera map
Map of cholera cases in Soho, London, 1854. Source: Wikimedia Commons.

John Snow, known as the father of epidemiology, was born on March 15, 1813. This week, we honor the birthday of the first true disease detective.

The Story of the Broad Street Pump

London, 1854: A cramped Soho neighborhood teems with people and animals living in cramped and dirty quarters. A deadly outbreak of cholera is spreading. Doctors and scientists believe it’s caused by “miasma,” or bad air. They theorize that particles from rotting matter and waste are getting into the air and making people sick.

Enter John Snow. An accomplished physician, he becomes convinced that something other than the air might be responsible for the illness. Through carefully mapping the outbreak, he finds that everyone affected has a single connection in common: they have all retrieved water from the local Broad Street pump.

On September 8, 1854, Snow tests his theory by removing the pump’s handle, effectively stopping the outbreak, proving his theory, and opening the door to modern epidemiology.

Valuable Lessons for a Modern Age

In 1854, John Snow was the first to use maps and records to track the spread of a disease back to its source. Today, his ideas provide the foundation for how we find and stop disease all over the world.

We have better, more modern tools now for identifying and tracking illness, like access to state-of-the-art labs and computer systems. We have in-depth knowledge of germs and how they spread. But when we train today’s disease detectives, we still return to the basics. CDC disease detectives are trained to look for clues by asking:

  • WHO is sick?
  • WHAT are their symptoms?
  • WHEN did they get sick?
  • WHERE could they have been exposed to the cause of the illness?

We live in a world where disease can travel across the globe in a matter of hours. This means we must not only apply these basic lessons of epidemiology, but we must constantly be looking for ways to find better answers, faster.

Disease Detectives Make a DifferenceEpidemic Intelligence Service

When outbreaks or other threats emerge, CDC’s disease detectives, some of whom are trained through our Epidemic Intelligence Service (EIS), are on the scene. These boots-on-the ground staff, called EIS officers, support over 100 public health investigations (Epi-Aids) each year in the U.S. and worldwide.

CDC’s disease detectives have been instrumental in tracking down threats like:

Anthrax: During the 2001 anthrax outbreak among U.S. postal workers, disease detectives investigated the route of contaminated envelopes and how workers became infected.

E. coli: For the first time, disease detectives conclusively showed that flour was the source of a 2016 E. coli outbreak. Millions of pounds of flour were taken off the shelves, including flour-containing products like bread, cake, and muffin mixes.

Seoul virus: Disease detectives have been working to track and stop an outbreak of Seoul virus, an emerging rodent-borne hantavirus, involving home-based rat breeders this year. The outbreak was first identified after two Wisconsin rat breeders became ill in December and, as of March 13, the investigation has so far included rat-breeding facilities in 15 states, with 17 people infected in seven states.

Like Snow’s map that revealed cases of cholera congregated around the Broad Street pump, we must keep tabs on where and how disease is spreading. Once the source of disease is identified, it is crucial to develop and implement interventions to help prevent people from getting sick. We must remain innovative and creative, like Snow when he removed the handle of the Broad Street pump to stop disease at the source.

References

West Nile to Zika: How One Virus Helped New York City Prepare for Another

New York City helicopter used for larviciding.

No one told the Aedes mosquito that New York is the city that never sleeps.

The type of mosquito that can spread Zika virus (Zika) is most active during the day and hides at night when our city’s mosquito control efforts are in full swing, meaning that our scientists had to find a way to reach it during pre-dawn hours. The solution? Wake it up, force it to take flight, and then kill it.

This is just one of many innovations New York is using to bolster the fight against Zika.

A tale of two mosquitoes

By the time the Zika outbreak was making news, causing birth defects and threatening pregnant women, New York City already had over a decade of experience in tackling mosquito problems related to the spread of West Nile virus. In facing Zika, we have been able to apply many of our existing resources and lessons learned from the West Nile virus response.

However, the mosquito that carries Zika is different than the one that carries West Nile virus, and it needs to be handled differently. New York is home to Aedes albopictus, which has been known to carry Zika – although, unlike the Aedes aegypti of the south, it has not yet been determined how likely Aedes albopictus is to spread the virus to humans in the United States. Because this is still unknown, people need to protect themselves.

To find out more about the risks, we need to catch the mosquitoes and test them. But we can’t use the same traps to catch the Aedes albopictus that we use to catch the West Nile virus-carrying Culex. Culex mosquitoes can be trapped with a combination of carbon dioxide and light. Being daytime creatures that prey mostly on people, Aedes albopictus don’t fall for the same tricks. So we developed traps that use human pheromones to lure them in.

Building on what we have

Aedes albopictus mosquito feeding.
Aedes albopictus mosquito

Meanwhile, some of the things we have always done for West Nile virus work well in the current response.

We know from previous mosquito-control efforts that pesticides are a last resort. Although there are lots of ways to kill a mosquito, West Nile virus taught us that an effective response takes cooperation on many fronts. In New York, we have laboratories for testing, disease control experts to track cases in people, and a call center that manages tests and information from clinicians. Our communication department gets the word out because the best thing we can do for viruses like West Nile and Zika is educate people about how to prevent mosquito bites – wearing the right repellent, removing standing water, and staying indoors when you can.

Many of the resources we acquired for fighting West Nile virus are proving indispensable for fighting Zika. Ten years ago, we got a hand-me-down helicopter from the NYPD, and we’ve been able to use this for aerial spraying over marshlands and unpopulated areas. In the city, we use the same late-night spray trucks. A police car moves ahead of the truck, warning anyone who may still be out on the street. The distinctly New York voice bellowing from the loudspeaker (that of retired assistant commissioner Allan Goldberg) is even the same one we’ve always used.

 Sharing what we know

Zika presents us with a very steep learning curve, and it reinforces the need for transparent communication. We’ve set up an interactive website where we can share what we’re discovering with the public. We put out data on a weekly basis: people can zoom in and out on their screens to see where we’re finding mosquitoes. We want everyone to understand about the preventive work we’re doing to help keep Zika at bay.

The complex nature of Zika reveals the strongest and weakest points of the public health system. One thing in particular public health has always struggled with is how to change people’s behavior, which is critical and must happen if we want to stop Zika. We really hope that pregnant women or women who plan to become pregnant will not travel to areas with Zika, but it’s hard to stop people from visiting family or simply enjoying the world.

So far, all of the reported Zika cases in New York – including, as of August, 49 among pregnant women – have been the result of global travel. But just because we haven’t seen local transmission doesn’t mean the potential isn’t there.

This is why we’ve expanded our efforts by hiring extra staff and extending the areas where we do mosquito control and education. We need to continue to collaborate across agencies and in the field – and, in fact, all over the world – to manage a complex response that touches on so many areas. Working together and staying vigilant is our only hope for getting – and staying – ahead of this potentially devastating disease.

Read our other National Preparedness Month blogs:

 

Zika, Mosquitoes, and Standing Water

Zika, Mosquitoes, and Standing Water

With spring weather and mosquito season coming soon in the United States, the Zika virus – and the mosquitoes that carry the virus – may be a major concern. Zika is currently affecting more than 30 countries and territories in the Americas and Pacific Islands. Zika virus is primarily spread through the bite of an infected Aedes aegypti mosquito. People and communities can take steps to reduce the number of mosquitoes in their homes and communities to protect themselves from Zika.

How Does Water Help Mosquitoes Breed?

Aedes aegypti is known as a “container-breeding mosquito” because it likes to lay eggs in and around standing water. Studies show that female mosquitoes prefer to lay eggs in water that collects or is stored in manmade containers.

Water-filled bioassay trays were used to attract resident female mosquitos to deposit their eggs, where they hatched, and from which the larvae were collected.Aedes aegypti mosquitoes lay eggs on the walls of water-filled containers. Eggs stick to containers like glue and remain attached until they are scrubbed off. The eggs can survive when they dry out—up to 8 months. When it rains or water covers the eggs, they hatch and become adults in about a week.

Reduce mosquitoes at home

Here are a couple of steps you can take to prevent mosquitoes from living and breeding around your home.

Remove standing water

Keep mosquitoes from laying eggs inside and outside of your home. Items in and around people’s homes can collect water. Once a week, empty and scrub, turn over, cover, or throw out containers that hold water, such as

  • Vases
  • pet water bowls
  • flowerpot saucers
  • discarded tires
  • buckets
  • pool covers
  • birdbaths
  • trash cans, and
  • rain barrels.

These actions can help reduce the number of mosquitoes around areas where people live.

Follow safe water storage tips

If water must be stored, tightly cover storage containers to prevent mosquitoes from getting inside and laying eggs.

Reduce mosquitoes in the community

Communities also can take steps to reduce the number of mosquitoes and the chances of spreading disease.

Build systems that distribute safe water

If people have access to clean and safe water in their communities, they will not need to store it in and around their homes. Research has shown that when community-wide distribution systems are built, the number of mosquitoes decreases, because water is not being stored near areas where people live.

Improve sanitation

When water is contaminated with organic matter (for example, human or animal waste, grasses, and leaves), the chances that mosquito larvae will survive may increase because contaminated matter provides food for larvae to eat. Sanitation departments and wastewater treatment plants remove organic wastes and treat water with chlorine or other disinfectants. These activities may decrease mosquito populations and, simultaneously, prevent diarrheal diseases.

*Basic sanitation includes access to facilities for the safe disposal of human waste, and the ability to maintain hygienic conditions, through services such as garbage collection, industrial/hazardous waste management, and wastewater treatment and disposal.

Water, sanitation, and hygiene* (WASH) are critical to keep people healthy and prevent the spread of many different disease, including Zika. World Water Day recognizes the importance of safe drinking water and improved sanitation and hygiene in the health of our world’s population.

Learn more about World Water Day at www.unwater.org/worldwaterday and visit www.cdc.gov/healthywater/global for more information about CDC’s efforts to ensure global access to improved water, sanitation, and hygiene.

For more information on the Zika virus, and for the latest updates, visit www.cdc.gov/zika.

Zika, Mosquitoes, and Standing Water

Zika, Mosquitoes, and Standing Water

With spring weather and mosquito season coming soon in the United States, the Zika virus – and the mosquitoes that carry the virus – may be a major concern. Zika is currently affecting more than 30 countries and territories in the Americas and Pacific Islands. Zika virus is primarily spread through the bite of an infected Aedes aegypti mosquito. People and communities can take steps to reduce the number of mosquitoes in their homes and communities to protect themselves from Zika.

How Does Water Help Mosquitoes Breed?

Aedes aegypti is known as a “container-breeding mosquito” because it likes to lay eggs in and around standing water. Studies show that female mosquitoes prefer to lay eggs in water that collects or is stored in manmade containers.

Water-filled bioassay trays were used to attract resident female mosquitos to deposit their eggs, where they hatched, and from which the larvae were collected.Aedes aegypti mosquitoes lay eggs on the walls of water-filled containers. Eggs stick to containers like glue and remain attached until they are scrubbed off. The eggs can survive when they dry out—up to 8 months. When it rains or water covers the eggs, they hatch and become adults in about a week.

Reduce mosquitoes at home

Here are a couple of steps you can take to prevent mosquitoes from living and breeding around your home.

Remove standing water

Keep mosquitoes from laying eggs inside and outside of your home. Items in and around people’s homes can collect water. Once a week, empty and scrub, turn over, cover, or throw out containers that hold water, such as

  • Vases
  • pet water bowls
  • flowerpot saucers
  • discarded tires
  • buckets
  • pool covers
  • birdbaths
  • trash cans, and
  • rain barrels.

These actions can help reduce the number of mosquitoes around areas where people live.

Follow safe water storage tips

If water must be stored, tightly cover storage containers to prevent mosquitoes from getting inside and laying eggs.

Reduce mosquitoes in the community

Communities also can take steps to reduce the number of mosquitoes and the chances of spreading disease.

Build systems that distribute safe water

If people have access to clean and safe water in their communities, they will not need to store it in and around their homes. Research has shown that when community-wide distribution systems are built, the number of mosquitoes decreases, because water is not being stored near areas where people live.

Improve sanitation

When water is contaminated with organic matter (for example, human or animal waste, grasses, and leaves), the chances that mosquito larvae will survive may increase because contaminated matter provides food for larvae to eat. Sanitation departments and wastewater treatment plants remove organic wastes and treat water with chlorine or other disinfectants. These activities may decrease mosquito populations and, simultaneously, prevent diarrheal diseases.

*Basic sanitation includes access to facilities for the safe disposal of human waste, and the ability to maintain hygienic conditions, through services such as garbage collection, industrial/hazardous waste management, and wastewater treatment and disposal.

Water, sanitation, and hygiene* (WASH) are critical to keep people healthy and prevent the spread of many different disease, including Zika. World Water Day recognizes the importance of safe drinking water and improved sanitation and hygiene in the health of our world’s population.

Learn more about World Water Day at www.unwater.org/worldwaterday and visit www.cdc.gov/healthywater/global for more information about CDC’s efforts to ensure global access to improved water, sanitation, and hygiene.

For more information on the Zika virus, and for the latest updates, visit www.cdc.gov/zika.

5 Things You Really Need to Know About Zika

5 Things You Really Need to Know About Zika Virus

Outbreaks of Zika have been reported in tropical Africa, Southeast Asia, the Pacific Islands, and most recently in the Americas. Because the mosquitoes that spread Zika virus are found throughout the world, it is likely that outbreaks will continue to spread. Here are 5 things that you really need to know about the Zika virus.

Zika is primarily spread through the bite of an infected mosquito.

Many areas in the United States have the type of mosquitoes that can become infected with and spread Zika virus. To date, there have been no reports of Zika being spread by mosquitoes in the continental United States. However, cases have been reported in travelers to the United States. With the recent outbreaks in the Americas, the number of Zika cases among travelers visiting or returning to the United States will likely increase.

These mosquitoes are aggressive daytime biters. They also bite at night. The mosquitoes that spread Zika virus also spread dengue and chikungunya viruses.

The best way to prevent Zika is to prevent mosquito bites.Zika_prevent mosquito bites

Protect yourself from mosquitoes by wearing long-sleeved shirts and long pants. Stay in places with air conditioning or that use window and door screens to keep mosquitoes outside.  Sleep under a mosquito bed net if air conditioned or screened rooms are not available or if sleeping outdoors.

Use Environmental Protection Agency (EPA)-registered insect repellents. When used as directed, these insect repellents are proven safe and effective even for pregnant and breastfeeding women.

Do not use insect repellent on babies younger than 2 months old. Dress your child in clothing that covers arms and legs. Cover crib, stroller, and baby carrier with mosquito netting.

Read more about how to protect yourself from mosquito bites.

Infection with Zika during pregnancy is linked to birth defects in babies.

Waiting for a baby. Close-up of young pregnant woman touching her abdomen while sitting on the couchZika virus can pass from a mother to the fetus during pregnancy, but we are unsure of how often this occurs. There have been reports of a serious birth defect of the brain called microcephaly (a birth defect in which the size of a baby’s head is smaller than expected for age and sex) in babies of mothers who were infected with Zika virus while pregnant. Additional studies are needed to determine the degree to which Zika is linked with microcephaly. More lab testing and other studies are planned to learn more about the risks of Zika virus infection during pregnancy.

We expect that the course of Zika virus disease in pregnant women is similar to that in the general population. No evidence exists to suggest that pregnant women are more susceptible or experience more severe disease during pregnancy.

Because of the possible association between Zika infection and microcephaly, pregnant women should strictly follow steps to prevent mosquito bites.

Pregnant women should delay travel to areas where Zika is spreading.

Until more is known, CDC recommends that pregnant women consider postponing travel to any area where Zika virus is spreading. If you must travel to one of these areas, talk to your healthcare provider first and strictly follow steps to prevent mosquito bites during the trip.

If you have a male partner who lives in or has traveled to an area where Zika is spreading, either do not have sex or use condoms the right way every time during your pregnancy.

For women trying to get pregnant, before you or your male partner travel, talk to your healthcare provider about your plans to become pregnant and the risk of Zika virus infection. You and your male partner should strictly follow steps to prevent mosquito bites during the trip.

Returning travelers infected with Zika can spread the virus through mosquito bites.

Man using insect repellantDuring the first week of infection, Zika virus can be found in the blood and passed from an infected person to a mosquito through mosquito bites. The infected mosquito must live long enough for the virus to multiply and for the mosquito to bite another person.

Protect your family, friends, neighbors, and community! If you have traveled to a country where Zika has been found, make sure you take the same measures to protect yourself from mosquito bites at home as you would while traveling. Wear long-sleeved shirts and long pants , use insect repellant, and stay in places with air conditioning or that use window and door screens to keep mosquitoes outside.

For more information on the Zika virus, and for the latest updates, visit www.cdc.gov/zika.

From the Field: CDC’s Field Assignment Program

CEFO in North Carolina during the H1N1 response

When faced with unexpected outbreaks and emergencies like zoonotic plague, Ebola, or contaminated cilantro that causes cyclosporiasis, Career Epidemiology Field Officers (CEFOs) are the experts in the field. One of CDC’s newer field assignment programs, the CEFO program is made up of highly skilled professionals assigned to state, territorial, and local health departments across the country to strengthen nationwide epidemiologic capacity and public health preparedness. CEFOs accomplish this mission while supporting day-to-day operations and emergency response activities of health departments. Being in the field and embedded in the public health networks of the area, CEFOs are on the front lines where emergencies typically begin and end: the local level.

The CEFO program was launched in 2002 to boost public health surveillance, epidemiology, and response efforts following 9/11 and the 2001 anthrax attacks. As of November 2015, 34 CEFOs are assigned to 27 state, territorial, and local public health programs. CEFOs bring a direct CDC connection to the state and local level. Public health agencies request CEFO assistance for an initial 2-year commitment, after which they can extend annually. Selecting a CEFO with the right background and skillset for a specific agency’s needs is important for success.

What do CEFOs actually do? 
 Map of states with CEFOs in them. are shaded gray.Although CEFOs have diverse professional backgrounds (physicians, veterinarians, scientists, nurses, and health services), all are experts in applied epidemiology. CEFOs have either completed training through CDC’s Epidemic Intelligence Service (EIS) or have comparable practical experience. Agency assignments vary, but CEFO priorities include rapidly identifying and halting the spread of disease outbreaks and other public health threats. CEFO’s accomplish this mission through enhancement of public health surveillance, strengthening outbreak response, conducting epidemiologic investigations, and development of the public health workforce. They serve as liaisons between health departments, local and state emergency response partners, healthcare providers, and CDC. CEFOs also develop and implement jurisdictional preparedness plans for emergency situations. For instance, one CEFO is currently analyzing data to identify potential health threats and prioritize resource distribution following severe droughts in California. CEFOs use epidemiological tools to help guide public agencies towards fast and effective responses that can address the health needs of the community.

Do you want to be a CEFO?
According to CDC CEFO Supervisor, Brant Goode, CEFOs tend to be two things: highly personable and very intelligent. Though being a CEFO can be extremely rewarding, working as a CEFO does pose challenges. Goode provides a few tips to future CDC CEFOs:

  1. Utilize the data. Understanding the demographics and other aspects of a jurisdiction’s public health is a great way to tailor preparedness and response efforts to the population. Along with learning from healthcare providers and health department staff, using census and public health data to learn about the area can aid in planning and implementation.
  2. Be clear about roles. CEFOs are federal officers meant to strengthen a jurisdiction’s mission. Because CEFOs support both CDC and their jurisdiction, working well with diverse partners is crucial for success.
  3. Be comfortable with being uncomfortable. Working as a CEFO can be very rewarding, but also challenging. Going from the federal level to the state or local levels can come with a steep learning curve at an accelerated speed. CEFOs should be prepared to serve in emergency management roles.
  4. Accept agency support. The CDC, partnering jurisdictions, and fellow CEFOs can provide support to CEFOs in completing their mission. Utilize resources and refer to previous cases for best practices, as well as past mistakes, to improve efficiency and prevent “wheel reinvention.”

CEFOs serve as CDC’s frontline defense against public health threats. Through expertise in applied epidemiology, they continue to improve nationwide preparedness to respond to all types of public health emergencies.

Global Health Security Agenda

A man waiting in the airport watching a plane take off

The Plan for 2016: CDC and the President’s Global Health Security Agenda

2015 was a powerful reminder that a health threat anywhere is a health threat everywhere.  In 2016, CDC and partners are looking forward to continuing work on the President’s Global Health Security Agenda (GHSA), an initiative led by the Department of Health and Human Services.

In 2012, only 1 in 6 countries reported being fully prepared for disease outbreaks. As the Ebola epidemic in West Africa tragically demonstrated, it is often the countries with the fewest resources who are hit hardest by public health emergencies.  To better protect people everywhere, the United States has committed more than $1 billion over the next 5 years to help 31 countries better prepare for the health impacts of natural and man-made disasters.  More than half of this historic investment will focus on the continent of Africa to help prevent future outbreaks.

World map of pixels in gray and light gray
There are 31 GHSA countries: Bangladesh • Burkina Faso • Cameroon • Cambodia • Côte d’Ivoire • Democratic Republic of Congo • Ethiopia • Georgia • Ghana • Guinea • Haiti • India • Indonesia • Jordan • Kazakhstan • Kenya • Laos • Liberia • Malaysia • Mali • Mozambique • Pakistan • Peru • Rwanda • Senegal • Sierra Leone • Tanzania • Thailand • Uganda • Ukraine • Vietnam

Global Health Security Agenda Goals

The vision of GHSA is to stop disease outbreaks as quickly as possible.  Partners will work together to build a global network that can respond rapidly and effectively to disease outbreaks and help countries build their own capacity to prevent, detect, and respond to public health emergencies.

The GHSA focuses on accelerating progress toward a world safe from disease threats by supporting enhanced surveillance and biosecurity systems, immunization campaigns, and curtailing antimicrobial resistance. Establishing national laboratory and disease reporting systems will help detect threats early.  In addition to building epidemiologic and laboratory workforce capacity, GHSA also focuses on incident management system training and establishing emergency operations centers around the globe.

As President Obama said at the Global Health Security Agenda Summit in 2014, “We issued a challenge to ourselves and to all nations of the world to make concrete pledges towards three key goals:  prevent, detect, and respond.  We have to prevent outbreaks by reducing risks.  We need to detect threats immediately wherever they arise.  And we need to respond rapidly and effectively when we see something happening, so that we can save lives and avert even larger outbreaks.”

CDC’s Role in Global Health Security
CDC is improving preparedness and response internationally by building close relationships with ministries of health and other public health partners abroad to encourage public health and emergency management capacity building. The agency also provides GHSA countries with resources such as funds, administrative support, and dedicated personnel, including experts in emergency response, electronic surveillance systems, and specific health threats. CDC also links emergency response efforts to recovery efforts to ensure systems and processes that have been put in place for one response can be ready for the next public health emergency.A person is giving another person a vaccine.

Ebola has reminded us that  to protect its citizens, each country should be equipped with a core set of public health capabilities to detect a threat when it emerges, respond rapidly and effectively, and prevent it wherever possible. All countries need to be prepared, since disease monitoring and emergency response begin at the local level.  Local responses will be quicker, more efficient, and more cost-effective than responding from a great distance. However, epidemics do not stay within borders and are not the problem of individual countries or regions. GHSA is an important step toward helping build capacity in other countries and ensuring that when national capacities are overwhelmed, the world moves immediately and decisively to contain the outbreak.

Ebola Response: Year in Review

A person washing their hands at a water station in West Africa

Throughout the month of December, Public Health Matters is conducting a series of year-in-review posts of some of the most impactful disease outbreaks of 2015. These posts will give you a glimpse of the work CDC is doing to prevent, identify, and respond to public health threats.

Getting to Zero

Getting to Zero was a theme and goal that dominated much of CDC’s attention in 2015. In January 2015, The World Health Organization reported that the Ebola epidemic had reached a turning point with the most impacted countries, Liberia, Guinea and Sierra Leone, seeing declines in the number of new cases of Ebola.  This turning point came after a year of battling the worst Ebola outbreak in history—resulting in over 20,000 cases by December 2014.

While the spread of the disease and U.S. media attention was at its peak in 2014, some of CDC’s most impactful and important work took place in 2015. This year’s response to the Ebola epidemic was marked with many challenges and accomplishments, new discoveries, and continuous hard work by hundreds of CDC staff. The dedication of CDC and its partners throughout the year has also led to the successful end of widespread Ebola transmission in Liberia and Sierra Leone.

Ebola Vaccine Trials

In April 2015, CDC, in partnership with The College of Medicine and Allied Health Sciences, University of Sierra Leone, and the Sierra Leone Ministry of Health and Sanitation, began a clinical trial to test the potential of a new vaccine to protect against the Ebola virus. This vaccine trial, known as Sierra Leone Trial to Introduce a Vaccine against Ebola (STRIVE), is designed to help protect against Zaire ebolavirus, the virus that is causing the current outbreak in West Africa.

Person getting a vaccine“A safe and effective vaccine would be a very important tool to stop Ebola in the future, and the front-line workers who are volunteering to participate are making a decision that could benefit health care professionals and communities wherever Ebola is a risk,” said CDC Director Tom Frieden, M.D., M.P.H.  “We hope this vaccine will be proven effective but in the meantime we must continue doing everything necessary to stop this epidemic —find every case, isolate and treat, safely and respectfully bury the dead, and find every single contact.”

This vaccine trial, along with a series of other vaccine trials taking place in West Africa, represents an important step in the response to the Ebola epidemic. In addition to the tireless efforts being made to completely eliminate Ebola cases, efforts to discover a vaccine could prevent an outbreak of this size in the future.

Leaving Lasting Infrastructures for Health

Programs like STRIVE seek to contribute not only to the future of Ebola prevention research, but also to the future of health care capabilities in the areas impacted by the Ebola epidemic. The STRIVE study is strengthening the existing research capacity of institutions in Sierra Leone by providing training and research experience to hundreds of staff to use now and for future studies.

CDC is leaving behind newly created emergency operation centers (EOC) in countries affected by widespread Ebola outbreaks.   The ministries of health will fully lead these new EOCs, which will provide a place to train healthcare workers to be better prepared to conduct outbreak surveillance and response.

Additionally, 2015 brought the official announcement of plans to create the African Centres for Disease Control and Prevention (African CDC). First proposed in 2013, the African CDC will seek ongoing collaboration with other public health entities across the continent and the world to elevate health outcomes for all citizens. Partners will assist by implementing activities, supporting the establishment of regional collaborating centers, advising the African CDC leadership and staff, and providing technical assistance.

Celebrate the Successes, Look to the Future

2015 brought significant progress in the Ebola response. Yet, while the successes and improvements made to public health infrastructure in West Africa are important to celebrate, the work continues to get to zero and end the largest Ebola outbreak in history.

As we draw closer to our goal of zero cases of Ebola, we are reminded of how critical it is to identify, prevent, and respond to outbreaks to prevent future epidemics of this magnitude.

Year in Review: Measles Linked to Disneyland

mouse helium balloons

 

 

 

 

 

 

 

 

 

 

 

Throughout the month of December, Public Health Matters is conducting a series of year-in-review posts of some of the most impactful disease outbreaks of 2015. These posts will help explain how CDC is working to prevent, identify, and respond to these outbreaks. Measles infiographic

Measles in Disneyland

After an uncharacteristically high number of measles cases in late 2014, the highly publicized California measles outbreak hit the media early this year.  Linked to Disneyland Resort Theme Parks in California the outbreak quickly became a multi-state public health incident that resulted in a total of 147 cases. Cases related to this outbreak were identified in seven states in the U.S., as well as Mexico and Canada.

Attention to this outbreak was further fueled by the interest surrounding vaccinations. Among the reported measles cases, the majority of patients were unvaccinated or had an unknown or undocumented vaccination status.

Why a Measles Outbreak in the U.S. is a Big Deal

In 2000, the United States declared that measles was eliminated from this country. The elimination of measles in the U.S. was due to a highly effective measles vaccine, a strong vaccination program that achieves high vaccine coverage in children, and a strong public health system for detecting and responding to measles cases and outbreaks.

Before a measles vaccine became available in 1963, 3 to 4 million people in the United States were infected with measles each year, resulting in an estimated 48,000 hospitalizations and 400 to 500 deaths.  Most people in the U.S. today are protected against measles through vaccination, so measles cases are uncommon compared to the number of cases before a vaccine was available. However, the risk of measles re-establishing itself as a prominent disease in the U.S. is possible—especially if vaccine coverage levels drop.

Today, measles is still endemic in many parts of the world, and measles outbreaks in the U.S. occur when measles is brought into the United States by unvaccinated travelers (Americans or foreign visitors) who get measles while they are in other countries. These travelers can spread measles to other people who are not protected against the disease, which sometimes leads to outbreaks. While the source of the Disneyland-associated measles outbreak was not identified, it is likely that a traveler (or more than one traveler) who was infected with measles overseas visited one or both of the Disney parks in December during their infectious period and infected other visitors to the park.

Measles: a Serious Sickness

Measles is extremely contagious. It is so contagious that if one person has it, 90% of the people close to the person who are not immune will be infected. You can catch measles just by being in the same room as a person with measles. Even if the infected person has left the room, the virus can live for up to two hours in an airspace where the infected person coughed or sneezed. The measles virus lives in the nose and throat mucus of an infected person, and can spread to others through coughing and sneezing.

Common symptoms of measles include, high fever, cough, runny nose, red, watery eyes, and a rash 3-5 days after symptoms begin. In some cases complications from measles can result in pneumonia, encephalitis (swelling of the brain), and death.

People at high risk for severe illness and complications from measles include, infants and children under 5 years of age, adults over the age of 20, pregnant women, and people with compromised immune systems.

What can be done to protect the public from measles outbreaks?

State and local health departments lead investigations of measles cases and outbreaks when they occur. CDC helps and supports health departments in these investigations and continually gathers data reported by states on confirmed measles cases to provide evaluation and monitoring from a national perspective.

High sustained measles vaccine coverage and rapid public health response are critical for preventing and controlling measles cases and outbreaks. It is possible to get rid of measles in the U.S. completely, but the first step is to eliminate measles from each country and region of the world. Once this happens, there will be no place from which measles can spread.

Until measles is eliminated worldwide, it remains a risk to any unvaccinated person exposed to the virus. Do your part to protect yourself, your family, and those around you from measles and make sure you and everyone in your family who is eligible gets vaccinated. The best protection against measles is measles-mumps-rubella (MMR) vaccine. MMR vaccine provides long-lasting protection against all strains of measles.

To learn more about measles, the MMR vaccine, and CDC’s efforts to reduce the number of measles case worldwide visit CDC’s Measles webpage.

 

Keeping Cool Under Pressure: NYC Legionnaires’ Disease Outbreak, Summer 2015

An outdoor HVAC air conditioner unit located on a high-floor porch of a midtown Manhattan skyscraper. In the summertime when the weather is hot, having air conditioning to help keep you cool can be a sweet relief. Have you ever felt a fine mist when walking past large buildings in the heat of the summer? That mist may have been water droplets from rooftop cooling towers that keep large air conditioning systems―like those found in hotels―running efficiently, even when temperatures are soaring outside. When these cooling towers are not properly maintained, they can become a home for Legionella bacteria, which thrive in untreated warm water. If people with certain health risks breathe in water droplets contaminated with these bacteria, they may develop Legionnaires’ disease. If people are getting sick with Legionnaires’ disease, how can health officials find out the source of the bacteria? A team of city, state, and CDC epidemiologists (disease detectives), laboratory scientists, and environmental health experts was able to do just that with an outbreak this summer in New York City.

Recognizing the Outbreak

Legionella bacteria are found naturally in fresh water and can live in most any warm water that isn’t properly treated with chemicals. Most people exposed to Legionella bacteria don’t get sick, but those who are older or already have health problems are at risk for developing Legionnaires’ disease. It’s not surprising for large cities to report several cases of the disease every year. However, epidemiologists are always on the lookout for an increase in cases that might suggest an outbreak of the disease. This past July, after noticing a spike in reports from clinics and hospitals in the Bronx, New York City investigators sprang into action.

Identifying the Source

CDC scientist testing sample from cooling tower next to image of sampling text.
CDC’s Danielle Mills samples a cooling tower in the Bronx. Inset: Checking pH of a cooling tower.

After mapping the places of work and residence of all the patients identified, the investigators noticed a pattern that indicated the source was likely a cooling tower. Then, using state-of-the-art computer modeling programs, the geographic area most likely to contain the contaminated cooling tower was identified. A team of environmental health experts from New York and CDC then collected samples from every cooling tower in that area and sent those samples to public health laboratories. Legionella are very challenging bacteria to work with, but after weeks of testing, city, state, and CDC laboratories were able to solve the mystery. The DNA “fingerprint” from the bacteria found in each of the patients was identical to that of the bacteria found in one of the cooling towers, confirming that it was the specific Legionella bacteria from that cooling tower that infected each of those patients.

Containing the Outbreak

Three scientist working in laboratory
Laboratory scientists from NYC’s Public Health Laboratory (Cathleen Carey and Taryn Burke) and CDC (Jeffrey Mercante) identify Legionella isolates.

Even before the source was confirmed, the suspected cooling tower and those in the surrounding area were cleaned and treated. Then officials worked with the building owners to ensure industry standards for treatment of their cooling tower were met. After weeks of a collaborative epidemiologic, environmental health, and laboratory investigation by the city, state, and CDC, the outbreak was declared over by New York City officials.

Keeping an Eye on Cooling Towers

With 128 people infected and 12 deaths attributable to the outbreak as of August 20, 2015, this was the largest outbreak of Legionnaires’ disease ever recorded in New York City. In response, the city passed new legislation that requires registration of all cooling towers and defines maintenance standards. The collaborative efforts of public health professionals from city, state, and federal agencies made it possible for this outbreak to be identified, solved, and contained as quickly as possible. Investigators like these, stationed all over the United States, at CDC, and across the globe are working every day to detect, respond to, and prevent public health threats. Now, THAT is cool.