That's what UC San Francisco medical student Joshua Lang wrote in his piece, With Summer Coming, Can the Zika Virus Be Contained?, published April 14 in The New Yorker.
Meanwhile, at UC Davis, plans are underway for a public "Zika Public Awareness Symposium," set Thursday, May 26 from 6:30 to 8:30 p.m. in Room 1001 of Giedt Hall.
"It is very important that students and the public-at-large learn how to prevent a possible Zika epidemic as this is the first virus known to be transmitted both sexually and by mosquitoes," said coordinator Walter Leal, a chemical ecologist and professor in the UC Davis Department of Molecular and Cellular Biology. Leal, who collaborates with fellow mosquito researchers in his native Brazil, is the co-chair of the International Congress of Entomology (ICE) meeting, to take place Sept. 25-30, 2016 in Orlando, Fla.
"This symposium is important to host because Zika is a rapidly spreading across the globe so people need to be informed," said Amarita Singh, one of the 18 students organizing the symposium. "Recent studies have shown that this particular virus not only affects pregnant women, but is a threat to all. Since there is no vaccine or medication, it is better to educate now to help prevention."
"I became more aware of the disease when Professor Leal began to discuss it in our biochemistry class, which is what originally sparked my interest," Singh said. "After learning about how dangerous the disease was and the discovery of the first case in Yolo County, I decided to take the opportunity in organizing the symposium."
Singh added: "It is incredible how much research has been done on Zika virus in the short amount of time. I am hopeful that in the near future that a vaccine will be developed, but until then we should do everything in our power to prevent this horrible virus from spreading. My concerns are that people may not be well informed which allows the virus to spread even more rapidly."
Said James Warwick, also one of the student organizers: "I think one of the scariest things about Zika in the United States is the lack of public knowledge about it. The scientific community needs to research the virus and develop a vaccine, but can't without funding. And without public pressure, securing funding is going to be slow. Also, the sheer suddenness in which Zika has burst onto the global scene has left both scientific research and public knowledge behind. That is why we are hosting the symposium, to bring the public up to speed, update them on the current research, and to give them the knowledge they need to protect themselves against transmission. As a byproduct, public awareness will increase public pressure to get the world on the right track to stop the spread of Zika."
"The virus itself is extremely alarming," Warwick said. "It can cause extreme neurological and immunological defects, as we see in babies born to infected mothers. But the direct hosts' symptoms usually consist only of temporary pain, rashes, fever, and the like; and only one in four or so people infected with Zika become symptomatic. So there is a very real possibility that a person could be infected, not be aware of it, and potentially pass on the undetected infection to sexual partners or their children. This is made all the more plausible by the fact that many people have never heard of Zika."
A flier (below) distributed at the campuswide UC Davis Picnic Day noted that the "Zika virus is a risk to all of us, not just to pregnant women." At the May 26th symposium, folks will "learn the symptoms and learn the facts and science about Zika and how you can protect yourself from this disease."
The scientific-based symposium will include "expert panels and speakers throughout the United States and the world, including those working on the front lines of the Zika epidemic." Speakers will be announced soon.
Attendance to the symposium is free, but due to limited space, those planning to attend are asked to RSVP to firstname.lastname@example.org
Native Brazilian Walter Leal, chemical ecologist and professor in the UC Davis Department of Molecular and Cellular Biology, is there.
So is the mosquito.
At the symposium today, Constancia Ayres, research coordinator of the Oswaldo Cruz Foundation (Centro de Pesquisa Aggeu Magalhaes/FIOCRUZ, considered one of the oldest and most prestigious scientific research institutes in South America), reported that the common southern house mosquito, Culex quinquefasciatus, may be a potential vector of the Zika virus.
Studies in the Ayres lab confirmed that Culex quinquefasciatus infected with Zika (isolated from local patients) showed high transmission rate (as determined by virus replication in the salivary glands).
Of course, these studies were done in the lab, not the field, and this is the beginning of the research.
We asked medical entomologist William Reisen, editor of the Journal of Medical Entomology, and professor emeritus, Department of Pathology, Microbiology and Immunology, UC Davis School of Veterinary Medicine, about this.
"In California less than 3 percent of the Culex including Cx. quinquefasciatus have been found to feed on humans, even in cities like Los Angeles, where humans are the most numerous host," Reisen said in an email. "Therefore, even if they are susceptible to infection, the probability of a female feeding on humans to acquire and then refeed on humans to transmit would be 0.03 x 0.03 = 0.0009 or a rare event indeed. That said, there are areas of the world where quinquefasciatus feeds predominantly on humans in domestic settings. (See his research paper, Host Selection Patterns of Some Pakistan Mosquitoes (U.S. National Library of Medicine, National Institutes of Health).
In his research paper on Pakistan mosquitoes, Reisen mentions Culex pipiens fatigans, now known as Culex quinquefasciatus. Its feeding patterns "varied opportunistically with host availability," he wrote in the abstract. Resting in cattle sheds during the winter, it "fed on birds and bovids, changing to man and bovids during the spring and then to man and birds during summer."
Medical entomologist Thomas Scott, distinguished professor of entomology (now emeritus) of the UC Davis Department of Entomology and Nematology, is a global authority on Aedes aegypti, which transmits dengue, yellow fever, chikungunya and the Zika viruses.
"Vector competence studies in the lab is valuable information, but before we come to the conclusion that Culex quinquefasciatus is an important contributor to transmission of Zika virus, the lab results would need to be confirmed," Scott told us. "Other laboratories and appropriate field studies would need to be carried out in areas where Zika virus is being transmitted to confirm that this species is naturally infected and is regularly biting people. Although it is a potentially important discovery that would change they way we think about Zika virus transmission, it would be wise to carefully explore all of the details necessary to incriminate a mosquito vector before coming to a strong conclusion."
UC Davis medical entomologist Anthony Cornel of the Kearney Agricultural Research and Extension Center and UC Davis Department of Entomology and Nematology, weighed in: "I have to examine the vector competence data carefully to determine its infectivity dose relative to Aedes aegypti. If Culex quinquefasciatus does play an additional role in transmission then it would be of even greater concern because the threat of autochthonous transmission will occur in areas other than where Aedes aegypti is found in California. Culex quinquefasciatus also feed on people but do so at dusk and at night."
"Brazil could be facing a greater fight against the zika virus than previously feared as researchers investigate whether the common mosquito is transmitting the disease," Moraes wrote in the article, headlined "Brazilian Experts Investigate if 'Common Mosquito' is Transmitting Zika Virus."
"The Aedes aegypti species of mosquito was thought to be solely responsible for spreading the virus," Moraes pointed out. "But scientists are now studying whether the Culex mosquito--the variety (species) most commonly found in Brazil--could also be passing on the infection."
Constancia Ayres was quoted as saying: "This may be the reason for the virus replicating faster. The interaction of the mosquito with the virus may explain the epidemiological profile of disease transmission.”
Meanwhile, the headlines continue as research proceeds.
"The concern is that the Culex mosquito--which is 20 times more prevalent than the Aedes variety in Brazil-- might also play some role in the rapid spread of these viruses," Outbreak News Today noted. "Researchers hope to have some answers in a few weeks,"
Valor.com.br is hot on the story as well. Reporter Marina Hawk emphasized that the work was done in the lab, but field collection is underway.
The mosquito transmits the Zika virus, currently "the" hot medical topic.
But it also transmits dengue, yellow fever and chikungunya viruses.
“Dengue infects 400 million people worldwide each year, and 4 billion people or nearly half of the world's population are at risk for dengue,” says medical entomologist Thomas Scott, distinguished professor and now emeritus, UC Davis Department of Entomology and Nematology.
Scott, who has studied dengue more than 25 years and is recognized as the leading expert in the ecology and epidemiology of the disease, emphasizes that “There is no vaccine nor drug that is effective against this virus." There are four serotypes: DENV-1 through DENV-4.
Now for the groundbreaking news.
Scott and his colleagues just published a study in the Public Library of Science (PLOS), Neglected Tropical Diseases, that is sure to rock the world of everyone who has ever contracted dengue.
Well, yes, you can. "Lifetime of immunity" is false.
“Our most significant result from this study is that immunity to dengue viruses does not always provide perfect protection from reinfection,” Scott said. “The public health implications include evaluation of dengue vaccines, interpretation of a person's virus exposure history and susceptibility to new infections, and design of dengue surveillance programs.”
“Our data indicate that protection from homologous DENV re-infection may be incomplete in some circumstances, which provides context for the limited vaccine efficacy against DENV-2 in recent trials,” the research team wrote. “Further studies are warranted to confirm this phenomenon and to evaluate the potential role of incomplete homologous protection in DENV transmission dynamics.”
Former UC Davis researcher Steve Stoddard and senior author of the paper said it well:
“It has long been thought that infection with any one of the viruses produced lifetime immunity to that virus. This finding could help explain results of dengue vaccine trials that showed poor efficacy against one of the four serotype. It also has broad implications for vaccine development.”
The research team investigated the "validity of the fundamental assumption" by analyzing a large epidemic caused by a new strain of DENV-2 that invaded Iquitos, Peru, in 2010-2011, 15 years after the first outbreak of DENV-2 in the region.
The species has spread to at least seven counties in California since June 2013, says UC Davis medical entomologist Anthony Cornel of the UC Kearney Agricultural Research and Extension Center, Parlier, and the UC Davis Department of Entomology.
“It's an issue of great concern, especially as current control methods do not appear to be working well," says Cornel, who collaborates on research projects in Clovis, Fresno County, with the Consolidated Mosquito Abatement District. The district, based in Fresno, covers 1,058 square miles, including part of Kings County.
“We can't predict how far this mosquito will go in California,” he says, but it has spread “south of Fresno to San Diego. The furtherest site north is Madera in the Central Valley, but it's also been found in the more coastal area of Menlo Park in San Mateo.”
As far north as Sacramento?
“I don't want to exclude the possibility that it may spread as far north as Sacramento,” said Cornel, who collects, rears and researches mosquitoes from all over the world, including the United States, Mali, Cameroon, Comoros, Tanzania, South Africa and Brazil. “We need to see if it overwinters as eggs or adults or both.”
Infected Aedes aegypti can transmit dengue, yellow fever, Zika and chikungunya viruses. The Zika virus was first identified in Uganda in 1947 in rhesus monkeys, according to the World Health Organization. It was subsequently identified in humans in 1952 in Uganda and the United Republic of Tanzania. Outbreaks of Zika virus disease have been recorded in Africa, the Americas, Asia and the Pacific.
Although the mosquito species is in California, it's important to point out that there are no reported cases of locally transmitted Zika virus in the state or in contiguous United States, according to the Centers for Disease Control and Prevention. The cases have all involved travelers returning home from countries plagued with disease outbreaks.
Cornel and his colleagues published a 27-slide document, “Surveillance and Control of Aedes aegypti Mosquito in Clovis, Calif.,” on Feb. 8 in F1000 Research, http://f1000research.com/slides/5-149. They called attention to the widespread invasion and establishment of the species in California. The research, illustrated with maps, is the work of Cornel and Yoosook Lee of UC Davis; Stephen Dobson of the University of Kentucky; Corey Bansfield of MosqMate Inc. and Jodi Holeman, Mark Amireno, Charles Smith and Stephen Mulligan III of the Consolidated Mosquito Control District.
The California team collaborates with University of Kentucky scientists to develop novel control strategies. One trial involves coating male mosquitoes with insect growth regulators, which are passed on to the females. Males are also infested with a biopesticide or “a good bacteria-like organism,” Wolbachia. “The male transfers it to the female, which affects the ovaries and negatively affects immature development,” Cornel explains. “It's not new, but it's not been employed in large trials.”
The researchers target mosquito breeding sites, primarily yard drains. “Despite the drought and the elimination of visible bodies of water, such as bird baths, pet bowls and flower pots, there's a major issue: yard drains,” Cornel says. “Yard drains installed in new home developments empty into the gutter or street and are cryptic breeding sites for mosquitoes.” He speculates that these mosquitoes are breeding underground.
“These drains are not easily accessible and we can't see the mosquitoes,” Cornel points out. “We need to blow out the water and plug these yard drains to eliminate these breeding sites.” He suggests that cities everywhere address this public safety issue and “redesign the yard drains.”
It's crucial for the public to become involved, Cornel emphasizes. “We have to focus on public education. We have to get the message across to eliminate mosquito breeding sites. We can't go to every house. We must rely on the public to eliminate the breeding sites.”
It's possible—but he hopes not—that what is now a “mosquito nuisance” will result in a disease outbreak.
The mosquito-borne viral disease known as “breakbone fever,” is three times more prevalent than originally thought, according to a research paper published today in Nature and co-authored by dengue expert Thomas Scott of UC Davis.
In their research paper, titled “The Global Distribution and Burden of Dengue,” Scott and the 17 other team members estimated that 350 million people are infected each year--more than triple the World Health Organization’s current estimate of 50 to 100 million.
Professor Simon Hay of the University of Oxford led the research as part of the International Research Consortium on Dengue Risk Assessment, Management and Surveillance.
“Dengue takes an enormous toll on human health worldwide, with as many as 4 billion people at risk," said Scott, a UC Davis professor of entomology and worldwide expert on the epidemiology and prevention of dengue. He chairs the mosquito-borne disease modelling group in the Research and Policy for Infectious Disease Dynamics (RAPIDD) program of the Science and Technology Directory, Department of Homeland Security, Fogarty International Center, National Institutes of Health.
“The results of our study and infrastructure that created the dengue maps fill a critical gap in the battle against dengue,” said Scott, who maintains field research programs in Iquitos, Peru, and Khamphaeng Phet, Thailand. “Prior to this, without rigorously derived dengue estimates that can be continuously updated, it was not possible to know with confidence where and when to direct interventions for greatest potential impact or to objectively assess the effectiveness of regional and global control efforts. That kind of knowledge was among the most important missing information for developing enhanced dengue prevention programs.”
The highly infectious tropical and subtropical disease is spread by the bite of an infected female Aedes aegypti, a day-biting, limited flight-range mosquito that prefers human blood to develop its eggs. Dengue is caused by four distinct, but closely related, viruses. The most severe form of disease is life-threatening dengue hemorrhagic fever or DHF.
The researchers assembled known records of dengue occurrence worldwide and used a formal modelling framework to map the global distribution of dengue risk. They then paired the resulting risk map with detailed longitudinal information from dengue cohort studies and population surfaces to infer the public health burden of dengue in 2010.
“There are currently no licensed vaccines or specific therapeutics, and substantial vector control efforts have not stopped its rapid emergence and global spread,” the researchers wrote.
Dengue has now begun to appear along the southern border of the United States, including Texas. Florida has also reported cases of dengue.
Of the 96 million clinically apparent dengue infections, Asia bears 70 percent of the burden, the research paper revealed. India alone accounts for around one-third of all infections.