Hurricane preparation and response resource list

Hurricane preparation and response resource list | www.APHLblog.org

Updated September 15, 2017

In the wake of hurricanes Harvey and Irma, public health laboratories in affected regions will be busy testing for potential environmental contamination, monitoring for increased water- and mosquito-borne diseases, or repairing damage to their own facilities. APHL has activated its Incident Command System (ICS) to support member laboratories with their response. The ICS team is participating in CDC’s Emergency Operations Center (EOC) State/Local and Partner Conference Calls, and will assist member labs with their response, facilitate communications between CDC and member labs, and share lab needs/stories with policy makers and the public.

Below are helpful resources for those communities hit by the recent storms. Many of these resources are useful for any severe weather event, not just Hurricanes Harvey and Irma.

Preparing for and weathering the storm

Hurricanes, Preparation and Response, EPA
Hurricane Preparedness Checklist, FDA
Preparing for a Hurricane or Tropical Storm, CDC
Flooding Toolkit, National Public Health Information Coalition
Disaster Assistance.gov, US government platform for locating disaster-related resources
Federal Emergency Management Agency (FEMA) Toll-free FEMA hotline for survivors of Hurricane Harvey: 1-800-621-FEMA

Keeping your family and community healthy after the storm

Food Safety:
Food Safety Tips for Areas Affected by Hurricane Irma, USDA press release
Protect Food and Water Before, During and After a Storm, FDA

Infectious Diseases:
Emerging and Zoonotic Infectious Diseases, CDC
Vector-borne Diseases, CDC​​​​​​​
Waterborne Disease Prevention, CDC

Drinking Water:
Drinking Water Safety and Testing Information for Texas, Texas Commission on Environmental Quality (accredited labs for microbial testing of drinking water, advice for customers of public water systems, disinfecting your well, etc.)
Drinking Water Testing and Information for Houston, TX, City of Houston
Private Wells: What to Do after the Flood, EPA
Private Wells: Water-related Diseases and Contaminants, CDC
Health Department Laboratory, Drinking Water Testing and Information, City of Houston

Other:
Carbon Monoxide Poisoning – Clinical Guidance, CDC
Mold: Cleanup and Remediation, CDC
Mold: Flood Cleanup, EPA
Waste Management, EPA

Rebuilding and repair

Cleanup after a Hurricane, CDC
Status of Systems in Areas Affected by Harvey, Texas Commission on Environmental Quality – drinking water, waste water and sewage, residential wells, flood waters, water infrastructure

The post Hurricane preparation and response resource list appeared first on APHL Lab Blog.

Inside the public health lab Zika response: ‘It’s the great unknown as to how much longer this will go on’

Inside the public health lab Zika response | www.APHLblog.org

By Kim Krisberg

Public health laboratory scientists are well used to the preparations and demands that come with emerging disease threats. But Zika virus is different.

“With SARS, West Nile virus, H1N1 flu, mumps outbreaks — those came and were gone in a few months,” said Michael Pentella, PhD, director of the state public health laboratory at the Massachusetts Department of Public Health. “We’ve been ramping up and dealing with Zika for a long period of time now and there’s no end in sight.”

While the Aedes aegypti mosquito — the species by which Zika is most commonly spread — is not found in Massachusetts, the state’s public health lab began preparing for the disease in late 2015. At first, the pace of testing was fairly slow, Pentella said, with the lab receiving less than 20 specimens a week as of January. The weekly volume quickly ramped up to about 150 a week in February, then slowed around the time that officials began warning at-risk populations to avoid travel to high-transmission regions. As of early September, volume was back up, with about 130 specimens arriving at the Massachusetts state lab every week. Most of those specimens are coming from Massachusetts residents, but the lab is also providing testing for a handful of other states where Zika testing is not yet fully operational.

At the moment, Pentella said Zika testing is “by no means overwhelming” the lab’s capacity, though he said it is adding significantly to staff workload. He is worried, however, that if another health threat arises on top of Zika, it could quickly push the lab to capacity. For example, the same personnel who conduct Zika testing also perform influenza testing. So if the upcoming flu season is particularly bad or a new flu strain emerges as Zika demands continue inching upward, “I’m very worried about our ability to handle both at the same time,” Pentella said.

Public health systems, including labs, continually prepare and practice for the possibility of outbreaks and disasters, and staff are ready for the additional duties that come with understanding, monitoring and containing a dangerous pathogen. Still, effective and sustained response requires sufficient funding. And in the case of Zika — a complicated disease with multiple modes of transmission and the potential for devastating birth defects — that funding has hardly been forthcoming. As of Sept. 20, with more than 20,000 Zika cases confirmed in U.S. states and territories, including 43 locally acquired cases in U.S. states, Congress had yet to authorize emergency funding for Zika response.

The White House first submitted its request for $1.9 billion in emergency Zika funds back in February based on recommendations from the scientific and public health community. But instead of acting quickly on those recommendations, Congress deadlocked on the issue. To make matters worse, that inaction comes on top of years of declining public health preparedness funding at the federal level as well as declining state and local public health budgets. Inside a public health lab, that funding inaction can have an acute effect. The equipment and its maintenance are expensive, the training is complex and the skill set is competitive. Yet, public health labs are indispensable to combating a disease like Zika. They provide the data that shape and drive effective interventions and provide testing services for all residents, regardless of their ability to pay.

And even though the U.S. is well into mosquito season, public health officials like Pentella say federal emergency funding is still needed — urgently.

“We need to take the broader perspective and look longer term so we’re not constantly on this yo-yo of ramping up and ramping down because funding goes away,” he said. “[Federal Zika funding] is becoming more urgent every day. I see the possibility of us falling behind and it will limit our capacity to respond. It really is tying our hands when we need to have all hands on deck.”

Zika lab response: ‘We’re in a very tenuous place’

Today, thankfully, there is nationwide coverage for the three tests used to screen for Zika virus, with public health labs bearing the majority of the testing burden but some commercial and clinical labs receiving authorization from the Centers for Disease Control and Prevention (CDC) to test as well. What’s unique about Zika, however, is that it requires both molecular and serological diagnostics.

Inside the public health lab Zika response | www.APHLblog.orgOn the molecular side, nearly every public health lab in the country has been confirmed to screen for Zika via polymerase chain reaction (PCR) testing, which CDC recommends for symptomatic patients tested less than 14 days after the initial onset of symptoms as well as for asymptomatic pregnant women who may have been exposed to the mosquito-borne virus. A positive PCR requires no follow-up. If the result is negative, however, the next step is serological testing using the IgM Antibody Capture Enzyme-Linked Immunosorbent Assay (MAC-ELISA), which detects the antibodies the body uses to fend off Zika infection.

In addition to confirming a negative PCR result, the serological test is recommended for asymptomatic pregnant women tested 14 or more days after potential virus exposure as well as for symptomatic patients beyond the 14-day window from initial onset. The challenge is that the MAC-ELISA is incredibly complicated, the throughput takes days longer than PCR, and, in general, serological testing isn’t a typical component of a lab’s surge response.

Plus, many public health labs have either cut back or stopped ELISA testing altogether because of previous funding cuts, said Chris Mangal, director of public health preparedness and response at APHL. Those funding cuts meant many labs have had to spend valuable time and resources bringing their serological capacity back to the frontline. As of late summer, 43 public health labs could test for Zika using the MAC-ELISA.

“When Congress opts to not provide resources for these emerging threats, it has a big effect,” Mangal said. “Yes, they’re prepared by virtue of their membership in the [CDC Laboratory Response Network (LRN)], but you still have to keep replacing the gas in the gas tank, if you will. That one tank of gas won’t get you across the country.”

The MAC-ELISA may be the best way to identify Zika in asymptomatic patients, but it’s also incredibly nonspecific, said Kelly Wroblewski, director of infectious diseases at APHL. In other words, the ELISA can also pick up antibodies to dengue and West Nile virus, which are in the same genus of viruses as Zika, and that means a positive ELISA for Zika has to be confirmed with yet another highly complex test — the plaque reduction neutralization test (PRNT) — that only a small number of public health labs and CDC have the capacity to perform.

Fortunately, Wroblewski said, most labs are currently able to handle the volume of specimens coming their way, with the exception of Florida, which is being bombarded with testing demands in the wake of local mosquito transmission.

As of September 20, the Florida Department of Health reported nearly 700 travel-related Zika cases and 89 non-travel-related cases, 87 of which involved pregnant women. It also reported that the department had conducted Zika testing for more than 7,815 people so far, noting that it only has the capacity to test 4,930 people for active Zika (PCR) and 8,364 for Zika antibodies (ELISA). Florida is home to both mosquito species that carry Zika and mosquito season in the Sunshine State is pretty much year-round.

“I think we’re in a very tenuous place,” Wroblewski said. “This isn’t going to be something that goes away after mosquito season is over. The public health system has done an amazing job responding without congressional support…but once the immediate danger is over, we’re very likely going to be in the same position rolling into next mosquito season.”

Labs in action: High-risk to Big Apple

Texas is considered a high-risk state for Zika, as it shares a border with Mexico and is home to both mosquito species that transmit the virus. As of September 20, Texas had 195 reported cases of Zika, all travel-related or transmitted via sexual contact.

At the state public health lab in the capital of Austin, Grace Kubin, PhD, director of the Laboratory Services Section at the Texas Department of State Health Services, said the volume of Zika-related specimens arriving at the Austin lab every day has doubled since February — as of early September, the volume was about 50 a day. However, that number would be a good bit larger if Texas wasn’t able to spread its Zika testing demands across its network of state and local public health labs. Kubin said almost all LRN public health labs in Texas can perform the more rapid PCR test, while Austin- and Dallas-based public health labs can perform serological testing, with labs in Houston and San Antonio working to bring serological capacity online as well.

“I’m happy to report that of the specimens coming in, we seem to be keeping up,” Kubin said. “We don’t have a backlog for either PCR or serology. We’ve gotten to a comfortable place right now, where we’re able to test whatever comes our way.”

Bringing testing capacity online had its challenges, Kubin reported. While the PCR process was fairly typical, the serological response, i.e. MAC-ELISA, was much more difficult. The MAC-ELISA, which received emergency use authorization in February, came with very specific biosafety guidelines that apply to serious or potentially lethal agents and complying with those guidelines is no easy task, Kubin said. Another challenge for labs is simply the time it takes to run a MAC-ELISA. For example, for the PCR test, the Austin lab can process a plate of 38 specimens in just a few hours. Serology also runs on a plate, but it holds just eight specimens and takes three days to process. To speed things up, the Austin lab set up a new system that allows it to process multiple serology plates each day.

“We have a little bit of extra room that maybe other labs don’t have,” Kubin said, noting that the Austin-based lab is one of the largest public health labs in the country. “Being such a large lab with a lot of testing divided out as far as molecular techniques being done in different areas…it allows us the ability to ask for additional help.”

Of course, once a local mosquito-transmitted Zika case is detected in Texas, testing demands will likely surge — a turn of events the Austin lab is preparing for at the same time it responds to daily Zika needs. Kubin said the Iowa state public health lab has already offered its assistance to Texas in case Zika demands begin to overwhelm the Lone Star state.

“Zika will continue to be the next new thing,” she said.

Inside the public health lab Zika response | www.APHLblog.orgThe Aedes aegypti mosquito doesn’t travel as far north as New York City, but its relative and potential Zika vector, the Aedes albopictus, does. According to the New York City Department of Health and Mental Hygiene as of Sept. 9, the city was home to 568 Zika cases, all travel-associated. Scott Hughes, PhD, associate director of environmental sciences at the New York City Public Health Laboratory, said the lab is receiving Zika-related specimens from about 50 patients every day. As of early September, the lab had performed testing for about 7,500 patients and received about 12,000 specimens. It began serological testing about two months ago.

In addition to human testing, the New York City lab is testing mosquitoes too, screening about 200 pools of trapped mosquitoes every week. Like other lab officials, Hughes said he is also concerned about the lab hitting capacity if another outbreak happens in the midst of Zika response.

“We really went from zero to 60 in a very short time,” Hughes said. An agency graphic shows that Zika testing requests for pregnant women went from zero in late March to nearly 2,500 in mid-July. “It’s the great unknown as to how much longer this will go on or whether this will become part of the everyday menu of tests we perform.”

Another Zika challenge both Hughes and Kubin mentioned was working with local obstetric/gynecology providers to receive specimens for testing, as such practices don’t typically work with public health labs. In New York City, the health department established a call center where providers can get more information; in Texas, public health officials partnered with professional pediatric and medical associations to disseminate information, among other measures. Out in California, Neil Silverman, MD, said educating medical providers is a “critical component” of Zika response.

A high-risk pregnancy specialist, Silverman is an obstetrician at the Center for Fetal Medicine & Women’s Ultrasound in Los Angeles and since February, has been serving as a perinatal consultant on Zika for the California Department of Public Health. In his consulting role, he helped craft messaging for obstetricians that not only educated on the nature and epidemiology of Zika, but on who should be tested and how to go about accessing testing. To paint a clearer picture of the process, Silverman pointed to his own experience.

Since the end of January, his practice has seen more than 200 pregnant women for Zika-related travel risks. At first, patient specimens were collected at the practice, then couriered to a nearby hospital lab, which then facilitated shipment to the county public health lab and on to CDC. Fortunately, the Los Angeles County public health lab now has Zika testing capability, but provider specimens are still couriered through a hospital lab. In particular, Silverman said, providers needed to know that any specimens sent to public health labs have to be accompanied with the proper epidemiologic paperwork; without it, testing can’t proceed.

“I get questions about Zika every single day,” he said about his practice. “The anxiety level is high and I think it’s only a matter of time before we start seeing some local cases.” As of September 16, California had no locally acquired Zika cases.

Silverman noted that as commercial labs have come online, it’s lessened the burden on California’s public health labs. But he also said that public health labs still offer one big advantage: they serve as a buffer against testing people who don’t need to be tested, making it easier for those truly at risk to access timely screening. Also, public health labs provide Zika testing for all those who need it, regardless of income or payer status, Silverman said, noting that one of the commercial labs his practice works with charges $165 upfront for Zika PCR testing.

“Our public health department and public health labs really are the boots on the ground,” he said. “They’re the sentinels when outbreaks occur, and it really is unfortunate that people don’t think of everything they do until there’s no money to fund them.”

Emergency funds still critically necessary  

Unfortunately, dealing with severe funding cuts and budget shortfalls while still maintaining core public health functions has become a mainstay of public health practice. However, in the face of a threat like Zika and its potential consequences for newborns and families, one would think emergency funding would be a slam-dunk.

Inside the public health lab Zika response | www.APHLblog.orgBut despite the concerted efforts of public health advocates, Congress has yet to authorize any emergency funding. In the face of such inaction, the White House redirected about $600 million away from Ebola response to fight Zika, and CDC was forced to redirect more than $44 million in Public Health Emergency Preparedness (PHEP) funds away from state and local health departments and toward national Zika response, though some of those funds returned to at-risk states and localities via CDC’s Epidemiology and Laboratory Capacity (ELC) program. The U.S. Department of Health and Human Services (HHS) redirected hundreds of millions of funds to domestic response as well, including $222 million that went to CDC.

But those are only stop-gap measures. In an August letter to key members of Congress, HHS Secretary Sylvia Burwell wrote that “CDC is on pace to virtually exhaust all of its domestic response funding by the end of the fiscal year.” Without additional funds, Burwell stated that CDC will have “severely limited” capacity to support mosquito control and surveillance and improve diagnostic Zika testing.

“Labs, like the rest of public health, are barely funded and because of that, they’re able to do a terrific job on a finite set of activities,” said Peter Kyriacopoulos, senior director of public policy at APHL. “For instance, they can do standard flu testing, but when there’s a pandemic flu outbreak they need additional resources because they’re working additional hours, using additional materials, using their machines more often, which leads to more maintenance…and all of that burden comes on top of their daily work. When you layer on top of that something like Ebola or Zika, that’s when the system begins to fray.”

In turn, federal emergency funding is still desperately needed, said Kyriacopoulos, who noted that APHL has had more meetings with congressional offices on Zika than it has on all other outbreaks combined. In particular, Kyriacopoulos worries that the inaction on Zika funding and resulting reprogramming of funds away from other public health priorities could set a dangerous precedent.

“Right now, we’re just kicking the can down the road,” he said. “This is not the way to effectively handle a public health crisis.”

Learn more about Zika:

September 30, 2014: As Ebola Arrived, the Texas Public Health Lab was Ready

This post was originally written for From The Lab Bench on October 2, 2014.
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By Michelle M. Forman, senior media specialist, APHL

The world is not as large as it often seems, and there are countless reminders that diseases are willing travelers. As US health officials saw Ebola ravage populations in West Africa, it became clear that we needed to prepare just in case this devastating disease arrived here. To much of the public health community in the US, the question of Ebola arriving wasn’t a matter “if” but rather “when.” And when it arrived, a coordinated response would be critical to rapid and thorough containment.

The first step was to ensure we were able to detect Ebola in suspect cases. In August, FDA issued an emergency use authorization (EUA) for an Ebola detection test developed by scientists at the Department of Defense (DoD) United States Army Research Institute of Infectious Disease (USAMRIID). Once the EUA was issued, CDC quickly began working with certain state and local public health laboratories, all members of the Laboratory Response Network (LRN), to determine which were best equipped to perform this testing.

September 29, 2014: As Ebola Arrived, the Texas Public Health Lab was Ready | www.APHLblog.org Select laboratories were approached by CDC to receive the test kit (Initial deployment of the test was limited to 12 LRN member laboratories but CDC continues to expand the number of qualified labs.); the Laboratory Services Section of the Texas Department State Health Services (the state public health lab) was an obvious choice given its stellar record in biothreat testing. Dr. Grace Kubin, director of the state public health lab, explained that they had the necessary instrumentation, four highly skilled biothreat staff well versed in handling select agents and a biothreat laboratory located in a separate building from the rest of the laboratory to ensure proper containment of threat agents. Once the Commissioner of the Texas Department of State Health Services, Dr. David Lakey, gave his approval, the laboratory immediately began preparing.

The first step was to inform all of the staff at the state laboratory. “I wanted them to hear it from me first, not the media,” said Dr. Kubin. She reviewed the extensive safety precautions that would be taken to ensure everyone’s safety. From there, she worked closely with her team to establish step-by-step guidelines for handling of an Ebola specimen from receipt to distribution of test results. Laboratory staff would work with state epidemiologists who would serve as the initial contact for suspect cases. Staff in the shipping office would be alerted when potential Ebola specimens were expected; just as with all biothreat specimens, they were not to open the package but instead contact biothreat lab staff to come pick it up.

None of this was atypical for this laboratory, though. Its biothreat team works routinely with far more dangerous select agents such as ricin and anthrax. This is what they do and they do it safely. Everything was already in place for their routine work; the possibility of Ebola meant tightening existing systems and keeping fear at bay.

September 29, 2014: As Ebola Arrived, the Texas Public Health Lab was Ready | www.APHLblog.orgAt the end of August they determined they were ready to test for Ebola.

Just over a month later, on Sunday, September 28, Dr. Kubin started receiving emails concerning a possible Ebola case in Dallas; later that evening CDC approved the Texas state public health lab to begin testing. On Monday the specimens were shipped to the state lab and to CDC for simultaneous testing. Early Tuesday morning the specimen arrived at the lab where staff were waiting to receive it.

This was their first specimen.

Just as instructed, the shipping staff alerted the biothreat laboratory staff of the package’s arrival without opening it. Testing began right away.

By early afternoon the biothreat lab staff obtained a presumptive positive result for Ebola. CDC laboratory staff, working simultaneously and performing additional testing, confirmed that finding shortly after.

Lab staff devoted the rest of the day to distributing information to Commissioner Lakey, the hospital staff, CDC and other key parties. Though the patient was already in treatment and under isolation, staff knew other potential cases could surface as the contact investigation progressed so they were poised to receive specimens any time of the day or night. “They’re used to getting calls at three AM saying there is a specimen that needs immediate testing,” explained Dr. Kubin.

While I expected my conversation with Dr. Kubin to end with her telling me that her staff felt a sense of accomplishment or relief that they successfully performed this critical test, she didn’t. For her staff, aside from the convoy of news trucks in their parking lot, this was all in a day’s work.

The Texas state public health lab acted quickly and efficiently, just as expected. Had the specimen been sent to any of the other approved LRN laboratories, we trust they would’ve done the same. They are strong, dedicated members of the public health system in this country. Because we have such a system in place, health officials and experts remain confident that this single Ebola case will not spiral into an outbreak.

When news of Ebola in Texas disappears, you’ll know the public health system did its job.

September 29, 2014: As Ebola Arrived, the Texas Public Health Lab was Ready | www.APHLblog.org

 

A man burns prickly pear to feed cattle during a drought in…



A man burns prickly pear to feed cattle during a drought in Texas. Photograph by Luis Marden, National Geographic Creative

A man burns prickly pear to feed cattle during a drought in…



A man burns prickly pear to feed cattle during a drought in Texas. Photograph by Luis Marden, National Geographic Creative

Women bask in the sun beside oil pumps, Padre Island, Texas….



Women bask in the sun beside oil pumps, Padre Island, Texas. April 1980.Photograph by Gordon Gahan, National Geographic Creative

Coming (Back) to America? What 2013 Can Teach Us About Dengue in the United States

jumbled picture of words related to dengue feverBy Tyler Sharp

2013 was a banner year for dengue in the United States: an outbreak with 22 associated cases was identified in Florida; another outbreak was detected in south Texas along the U.S./Mexico border;  Aedes aegypti, the most efficient mosquito vector of dengue, was detected in central-California; a locally acquired dengue case was detected outside of NYC; and Puerto Rico experienced a sizeable dengue epidemic that had been ongoing  since late 2012.  So, what’s next?  Is this par for the course, or was 2013 an anomaly?  In this blog, I’ll discuss the history of dengue in the U.S., what the future might hold, and what you can do to reduce your risk of getting infected while at home or abroad.

History of Dengue in the U.S.

world map of dengue infectionsDengue is a tropical illness that causes fever, body pain, severe headache and eye pain, and sometimes minor bleeding from the nose or gums.  Four different but related viruses can cause dengue, all of which are transmitted by mosquitoes of the Aedes genus.  Because immunity against one virus does not protect you from infection with the other three, you can get dengue up to four times in your life. Around 5% of dengue cases progress to severe dengue, which can result in severe bleeding, shock, and even death.  Although most Americans have never heard of dengue because there is not much of it in the continental United States, dengue is actually quite common throughout the tropics, where 400 million infections occurred in 2010.

Despite relatively low case counts in recent decades, dengue is no stranger to the United States.  Dr. Benjamin Rush, a signatory of the Declaration of Independence, documented a dengue outbreak in Philadelphia in 1780.  Ships arriving from foreign ports were bringing mosquitoes and infected people back to port cities in the U.S., where local outbreaks then followed.  This continued along the eastern seaboard and Gulf coast for the next 150+ years: an outbreak in 1873 affected an estimated 40,000 residents of New Orleans, and another in 1922 made its way through the entire Gulf coast.  The last recorded dengue outbreak in the continental U.S. occurred in 1945 when a soldier returning from Guyana to Louisiana brought the virus home with him, resulting in an outbreak in which 145 people were affected.

Aedes Eradication Campaign

black and white image of DDT being sprayedSo why were no dengue outbreaks identified in the U.S. between 1945 and now?  Most prominently, the chemical DDT was used beginning in the 1940s to nearly eliminate Aedes mosquitoes, which also transmit yellow fever and chikungunya, from the Americas.  However, before the mission was completed, the detrimental effect of DDT on the environment was made public and elimination efforts were halted.  Consequently, over the next several decades mosquito populations gradually re-established themselves in the U.S. and abroad.  As the burden of dengue in the tropics began to increase in the 1980s and 1990s and Americans began to travel internationally more frequently, more and more travelers began to return to the U.S. with the unwanted souvenir of dengue.

Present-day dengue in the U.S.

Following a large dengue epidemic in Mexico that spilled over into south Texas in 2005, an investigation revealed not only that stable populations of Aedes mosquitoes were established along the Texas side of the U.S.-Mexico border, but also that 39% of residents had been previously infected with a dengue virus.  Because several of these individuals had never left the United States, this demonstrated that dengue virus had been circulating in south Texas.

On the other side of the Gulf of Mexico, in 2009 a dengue outbreak was detected in Key West, Florida, which was likely caused by importation of the virus in a traveler returning from Central America.  The outbreak ultimately resulted in 5% of the small island community being infected.  Dengue cases resulting from infection in Florida continued to be detected in the area in 2010 and 2011, and one report suggested that the virus may have become established in the region.  Thankfully, no additional locally-acquired cases were reported in Key West in 2012, although dengue did pop up in Florida again in 2013. These outbreaks have made it clear that although rare, conditions do exist for localized outbreaks in parts of the U.S.

This week CDC Dengue Branch and co-investigators in Texas and New Mexico reported a locally acquired, dengue-related death in the continental United States.  Although the patient died from a rare complication of dengue called hemophagocytic lymphohistiocytosis, this is the third dengue-related death ever in the United States.  Although our investigation couldn’t confirm where the case-patient was infected, she hadn’t traveled out of the country recently, so she must have been infected either in New Mexico, where she was vacationing before she got sick, or in her home state of Texas. This case was a startling demonstration that there may be more dengue in the U.S. than we realize, and that physicians should be on the look-out for cases.

What’s next

Aedes aegypti mosquito speciesThe burden of dengue in the Americas has increased roughly 30-fold since 1950, and one study showed that dengue-related hospitalizations in the United States tripled between 2000 and 2007.  So, dengue cases will likely continue to show up in greater numbers in the U.S. until we have a safe and effective dengue vaccine or other intervention to prevent dengue.  Moreover, two mosquitoes capable of transmitting dengue, Aedes aegypti and Aedes albopictus, are present mostly in the southern United States, but have recently been found as far north as Chicago and New York.  Therefore the possibility of local outbreaks in the U.S. after infected travelers return home is real.  Nonetheless, factors such as population density, frequent use of air conditioning, and other lifestyle differences that limit our exposure to Aedes mosquitoes reduce the likelihood of sustained dengue outbreaks in the continental U.S.  Therefore, Americans are more likely to get dengue while traveling in Latin America, for example to large international events like the World Cup, than they are to get dengue at home.  Nonetheless, new introductions of the virus will continue, some of which will result in local dengue outbreaks.

What to do about it

To protect yourself against getting dengue, be aware of the risk of dengue while at home or traveling to the tropics, as well as the prevention approaches you can take to avoid mosquito bites (regular use of mosquito repellent, staying in buildings with air conditioning and/or window screens, seeking medical care if experiencing a fever during or soon after travel).  Residents of states where Aedes mosquitoes are present can reduce their risk of spreading the virus by disposing of, emptying or covering water containers that serve as mosquito breeding sites (e.g., trash, discarded tires, kiddie pools).  These strategies reduce the chances that a returning traveler could get bitten in the U.S. and create a local outbreak.  Lastly, having a pre-travel health care consultation with your health care provider or a travel medicine specialist can provide additional information about dengue and other travel-associated risks that weren’t covered here.

Although the world is preparing for the introduction of a dengue vaccine, it is likely to be at least a few years before one is commercially available.  Until that time, dengue will become more and more familiar to Americans, both at home and abroad.

Evening rush hour in Houston, Texas.Photograph by Clifton R….



Evening rush hour in Houston, Texas.Photograph by Clifton R. Adams, National Geographic

A dog rests on a couch in a store in Texas, 1992.Photograph by…



A dog rests on a couch in a store in Texas, 1992.Photograph by Bruce Dale, National Geographic