Researchers said these susceptibilities can happen anywhere. After Hurricane Katrina hit New Orleans, cases of West Nile disease doubled the next year. Climate change in Africa appears to be increasing cases of malaria. And the recent destruction in Houston, Florida and Puerto Rico due to hurricanes may usher in more infectious diseases in the years ahead.
According to a new study by researchers from the University of Colorado Anschutz Medical Campus. Aside from inflicting devastating natural disasters on often vulnerable communities, climate change can also spur outbreaks of infectious diseases like Zika , malaria and dengue fever,
"Climate change presents complex and wide-reaching threats to human health," said Cecilia Sorensen, MD, lead author of the study and the Living Closer Foundation Fellow in Climate and Health Policy at CU Anschutz. "It can amplify and unmask ecological and socio-political weaknesses and increase the risk of adverse health outcomes in socially vulnerable regions."
The study focused specifically on a magnitude 7.7 earthquake that struck coastal Ecuador in April 2016, coinciding with an exceptionally strong El Niño event. El Niños are associated with heavy rainfall and warmer air temperatures. They are also linked to outbreaks of dengue fever.
"We were seeing these viral symptoms in the wake of the quake," she said. "We noticed a huge spike in Zika cases where the earthquake occurred. Prior to this, there were only a handful of Zika cases in the whole country." In fact, the researchers found the number of Zika cases had increased 12-fold in the quake zone.
Zika virus is transmitted by mosquitos. Symptoms are usually mild but the infection can cause major abnormalities and even death in a developing fetus. Warmer temperatures and increased rainfall from the El Niño, along with a devastated infrastructure and an influx of people into larger cities, likely caused the spike in Zika cases, Sorensen said.
The researchers suggest El Niño created ideal conditions for Zika-carrying mosquitos to breed and make more copies of the Zika virus. The warmer temperatures and increased rainfall from El Niño have previously been associated with a higher likelihood of dengue outbreaks. Warmer temperatures can also accelerate viral replication in mosquitoes and influence mosquitos' development and breeding habits.
The team also believes an increase in water scarcity after the earthquake indirectly benefited mosquito development. The quake damaged municipal water systems, forcing people to store water in open containers outside their homes. These served as additional habitats for mosquito larvae.
Authors idea is to develop disease models that can use existing climate models to predict where these vectors will show up due to climate variability. Applying these new models to areas that have pre-existing social vulnerabilities could detect susceptible regions, allowing us to direct healthcare resources there ahead of time.