Zika may be the top contender in the public’s mind as the world’s biggest mosquito-borne disease threat, but some health workers in South America are seeing a worrying new counter-punch from malaria.
With much of the world’s attention on fighting the Zika virus, there have been significant strides in the effort to combat the aedes species of mosquito that transmits Zika, dengue fever and a host of other diseases. But this diversion may have led to some neglect in controlling the anopheles mosquito – the vector that transmits malaria.
Malaria is already endemic in Colombia, with 60 percent of the population living in areas at risk for the disease. But Doctors Without Borders (MSF) has recently detected an unusual rise in a particularly deadly strain of malaria in the South American nation, and there is reason to believe the trend also exists in other countries in the region.
According to a news release by MSF, Colombia experiences an outbreak of malaria every five or six years. The cycle is attributed to the El Niño phenomenon, which alters rainfall patterns that then increase the population of the anopheles mosquito that transmits the disease.
During the last outbreak in 2010, 71 percent of the more than 117,000 malaria cases reported in Colombia were caused by the vivax parasite – the type of malaria that is typical across Latin America. But this year, vivax was to blame for only 35 percent, while the majority (60 percent) of malaria cases were caused by the falciparum parasite.
“Both the falciparum and vivax strains of malaria can cause death…” reads the news release by Ana Zaratiegui, MSF’s head of medical operations in in Latin America. “[But] the falciparum malaria strain causes the most lethal form of the disease, cerebral malaria, and has a higher associated mortality rate, mainly in the most vulnerable groups, namely children, the elderly and pregnant women.”
Although treatment for both malaria strains is completely different, both are highly treatable if they are caught early on. The real problem is that the changing trend in malaria strains has come as a shock to health officials, who lack the resources needed to treat the new infections.
According to MSF, the Colombian Ministry of Health could not obtain any treatments for more than three months earlier this year. In an attempt to compensate, MSF donated over 20,000 treatments in May, which were distributed by local health workers in the most affected areas.
A similar shortage of medicine has afflicted neighboring Venezuela, where malaria cases have skyrocketed over the last few years almost as rapidly as the inflation rate. Although full treatment for the falciparum strain of malaria costs just several dollars, according to a New York Times report, there have drastic shortages of all malaria medications in Venezuela this year.
“Doctors say there is just a one-month supply of medicine available for the [falciparum]form of the disease,” said Dr. José Félix Oletta, a former Health Minister of Venezuela.
Across the region, the current malaria outbreak has ended, and the number of cases has leveled off around levels that are typical for endemic areas, according to MSF. If the new trend of falciparum malaria is confirmed, however, health officials will need to adapt their budgets and approaches before the next outbreak arrives.
For now, the cause of the new pattern – and the probability that it will happen again – remains somewhat of a mystery.
“The truth is that we really don’t know,” said the MSF report’s author, Ana Zaratiegui, in an interview with Humanosphere. “That is the question now – why are we seeing the falciparum strain more now, in this particular region?”
“It could be climatic,” Zaratiegui added, “but it could be other things as well. This is what we are working on, now, to try to answer this.”