Author Interviews, Dengue, PLoS, Zika / 04.02.2021 Interview with: Gregor J. Devine, Ph.D Mosquito Control LaboratoryQIMR Berghofer Medical Research Institute Brisbane, Queensland, Australia What is the background for this study? Scale of the problem: Dengue, Zika and chikungunya are all transmitted by the same mosquito species.  That mosquito, Aedes aegypti, is superbly adapted to the human, urban environment – it lays its eggs and develops in the standing water that collects in the myriad containers associated with modern living (plastic bottles, food packaging, buckets, planters, crumpled tarpaulins etc.). Unusually they rely almost entirely on human blood for their nutritional requirements and they subsequently bite multiple times during each egg laying cycle. That reliance on human blood means that they are usually found resting indoors, a behaviour that also offers them some protection from weather extremes and predators. Once infected, and having incubated the virus until it is transmissible, a mosquito that survives for just a couple of weeks can infect many humans within the same and neighbouring households. In poorer tropical urban environments with dense human populations, unscreened houses, no air-conditioning, and innumerable rain-filled containers to develop in, Aedes aegypti proliferates and so do those diseases, causing ca 400M annual infections of dengue alone by some estimates. The economic impact of the dengue, which normally causes a high fever, muscle and joint pains and nausea, is pronounced; especially in poor households with few savings and no welfare system. Every year, about 500,000 of those dengue cases develop into severe dengue, or dengue haemorrhagic fever (typified by plasma leakage, severe bleeding and organ impairment). There are about 25,000 deaths annually. mosquito-Aedes aegypti-feeding-human.jpgThe Zika pandemic of 2015-2016 resulted in 1000s of babies born with microcephaly and damage to their brains and eyes. For 1000s of other children, the impacts of Zika on their cognitive development did not manifest in their first, formative years.  Chikungunya is endemic in Asia and Africa but between 2010 and 2014, outbreaks and epidemics spread across the Indian Ocean, the Caribbean, the Americas and the Pacific Islands. It causes severe, often debilitating joint pain in infected patients. Those affected also suffer from headaches, fever, severe muscle pain and conjunctivitis. Joint pain can persist in subacute or chronic form for several months or even years, particularly in older patients. The ubiquity of the mosquito Aedes aegypti across the tropics and sub tropics ensures that further epidemics of Zika and chikungunya will occur, outside their usual ranges. It’s simply impossible to predict when that will occur. (more…)
Author Interviews, Infections, Vaccine Studies / 23.01.2019 Interview with: ValnevaThomas Lingelbach President & CEO of Valneva What is the background for this study? Would you briefly explain the significance of Chikungunya disease? Response: Chikungunya is a mosquito-borne viral disease caused by the Chikungunya virus (CHIKV), a Togaviridae virus, transmitted by Aedes mosquitoes. The chikungunya virus causes clinical illness in 72-92% of infected humans around four to seven days after an infected mosquito bite. People infected with chikungunya may suffer from acute onset of fever, debilitating joint and muscle pain, headache, nausea and rash, potentially developing into long-term, serious health impairments such as visual, neurological, heart and gastrointestinal manifestations that in some extreme cases can lead to fatalities. Chikungunya outbreaks have been reported in Asia, Africa, the Americas and Europe. As of 2017, there have been more than one million reported cases in the Americas. The medical burden is expected to grow as the CHIKV primary mosquito vectors continue to further spread geographically. Currently there are no preventive vaccines against Chikungunya making it a major threat to public health. We set out to develop VLA1553, a live-attenuated vaccine candidate, as a potential solution to the growing unmet need chikungunya poses. Our hope is that having a preventative vaccine for chikungunya will allow people living in endemic areas to have peace of mind while enjoying the outdoors. (more…)
FDA, Infections, Vaccine Studies / 08.05.2018 Interview with: Lisa Danzig, MD Chief Medical Office PaxVax Would you briefly explain what is meant by Chikungunya infection?  Whom does it primarily affect?  How is it transmitted and what the  complications? Response: Chikungunya is caused by the chikungunya virus (CHIKV), an arthropod-borne virus (arbovirus) spread by infected mosquitos. Infection with chikungunya virus results in severe, often debilitating joint pain in infected patients, known as arthralgia. Symptoms can include intense discomfort in joints, such as the wrists, fingers, ankles, and feet, in the knees and in the hips or shoulders. Those affected can also frequently suffer from headaches, fever, and severe muscle pain, rashes on the torso and limbs and swelling in one or more cervical lymph nodes. Individuals who are at a higher risk for contracting chikungunya include infants, elderly and those with chronic conditions. The virus is a small, spherical, enveloped, positive-strand RNA virus. The virus is transmitted by the Aedes aegypti and Aedes albopictus mosquito, which originated in Africa, first spreading to Asia and recently expanding to the western hemisphere.  Outbreaks are rapid and widespread.  In February 2005 a major outbreak of chikungunya occurred in the islands of the Indian Ocean after which over 1.9 million cases have been reported in India, Indonesia, Maldives, Myanmar and Thailand. Chikungunya spread has been identified in 45 countries in the Americas alone with more than 1.7 million suspected cases reported to the Pan American Health Organization since 2015, increasing the incidence of the disease and risk to U.S. travelers. In 2016 there were approximately 60,000 cases of chikungunya across India. Beyond the Indian subcontinent, the Caribbean, Central America and South America, inhabitants and travelers visiting sub-Saharan Africa and Southeast Asia are also at risk. (more…)
Author Interviews, Dengue, Infections, PLoS / 16.01.2015 Interview with: Jose R. Loaiza Smithsonian Tropical Research Institute, Panama City, Panama, Instituto de Investigaciones Científicas y Servicios de Alta Tecnología,  Universidad de Panamá, Ciudad de Panamá, Panamá   Medical Research: What is the background for this study? Response: The mosquito Aedes albopictus is a worldwide vector of both Dengue and Chikungunya viruses. This species invaded Panama in 2002, and it expanded across much of the country since that time. Our main goal was to determine the factors (e.g., ecological and non-ecological) associated with its expansion, and to comment on the implications for vector and disease control programs elsewhere in the American tropics. Medical Research: What are the main findings? Response: We found that road networks alone best predicted the distribution of Ae. albopictus in Panama over other variables such as population density and climate. Our data explain the invasion mode of this mosquito species on a local level and demonstrate a remarkable population expansion velocity across the country. Ae. albopictus is likely moving across the landscape as immature stages (i.e., larvae and pupae) in open water, such as used tires. (more…)