Earlier this week I returned from Brazil, a nation in crisis over the Zika virus epidemic. This public health calamity creates a perfect storm when combined with the economic and sociopolitical woes now facing South America’s largest country. The lack of fiscal resources and waning confidence in the current government present dire constraints in managing the current epidemic.

The Zika virus is a mosquito-borne infection that is asymptomatic in an estimated 4 of 5 cases. When Zika does cause illness, symptoms are generally mild, except for those already in a weakened state of health. Recent evidence suggests an association between pregnant women who contract Zika and birth defects, particularly microcephaly (for example, small head and brain size). In addition to infection by mosquitoes, sexual transmission of Zika is also possible and is of particular concern during pregnancy. There is also an association with Guillain-Barre syndrome, a secondary reaction to the virus that can cause debilitating weakness. No vaccination exists to prevent Zika, and there is no medical treatment.

In Brazil, somewhere between 500,000 and 1.5 million people are infected with Zika, according to a recent statement by its Health Ministry. Unfortunately, lack of funding makes it impossible to test all those who might have the illness, so there are certainly additional cases that have not been identified. Scientists are reportedly close to developing a commercial test to check for the disease, but even when a retail test does become available, for most people it will be cost-prohibitive.

In an effort to stem the epidemic, Brazil is working to mobilize 220,000 troops to go door to door to educate the population on preventive measures, including mitigation of stagnant water; to provide mosquito repellent to as many as 400,000 people; and to fumigate.

In desperation, Brazil’s embattled president, Dilma Rousseff, has even called upon clergy to mention Zika prevention during sermons. Also, Brazilian women have been advised to avoid pregnancy at this time. In speaking during Carnival with Alexey Bevilacqua, a native Brazilian and professional environmentalist, he said, “That’s never going to happen.”

Brazil’s greater ills have a long history. It is a vast region, replete with tropical forests and immense mineral and oil deposits. The Portuguese, who colonized the region, pushed aside or killed many of the 2 million indigenous Indians, often inadvertently with venereal disease and other European-sourced diseases. They then brought in 4 million African slaves who survived the crossing, from among the 10 million who were torn from their tribal communities. With slave labor, business interests have clear-cut forests, engaged in strip mining and operated enormous commercial farms focused on sugar, coffee and cattle.

When slavery was abolished in Brazil in 1888, little effort was made to integrate former slaves into society. As such, without housing or employment, most migrated to urban slums called “favelas.” Over 11 million Brazilians live in favelas today, the largest of which is in Rio de Janeiro, the city selected for the 2016 Summer Olympics.

Poverty, poor water supplies and weak public health systems are major factors that enable the spread of mosquito-borne illnesses. While in Brazil I stayed in the northeast, traditionally one of the poorest regions in Brazil and hardest hit by the Zika epidemic. Most mothers of children born with microcephaly have come from poor communities in this region. Favela neighborhoods are densely populated and residents can afford few protections. For most the price of insect repellent is beyond reach. Closing windows and instead using air conditioners is out of the question, as is purchasing protective clothing for doing manual labor outside.

Much began to change for the better in the late 1980s after the end of Brazil’s two-decades-long dictatorship. In fact, during the decade that ended two years ago, “it was the best time to live in Brazil,” according to Bevilacqua. The economy was good, there were many jobs and social benefits improved.

Now, on the heels of China’s slowing demand for natural resources, Brazil is in the midst of its longest- ever recession. The economy is expected to contract 8 percent this year, and Brazil’s commodity index has shrunk by 41 percent, while its currency was devalued by 31 percent during 2015.

At the same time, a bribery scandal implicated 32 members of the ruling political party. Impeachment proceedings began against Rousseff, both for not averting the bribery scandal and for misrepresenting the severity of the budget deficit.

Brazil is not alone. Throughout Central and South America, sub-Saharan Africa and in Polynesia, wealth and health disparities, poverty and poor public health infrastructure are widespread. Mosquito- borne illnesses including not only Zika, but also dengue and chikungunya continue to spread. As climate change advances and the world population grows and becomes more mobile, these illnesses will be found in new regions.

The Summer Olympics in Rio de Janeiro will highlight the critical need for global cooperation to find public health solutions for all concerned.

Ira Zunin, M.D., M.P.H., M.B.A., is medical director of Manakai o Malama Integrated Healthcare Group and Rehabilitation Center and CEO of Global Advisory Services Inc. Submit your questions to info@manakaiomalama.com.