The Zika epidemic may be over in Brazil…for now.
The Zika virus first made an appearance in South America in Brazil
in 2015, and continued its spread to other countries on the continent. The epidemic caused devastating neurological complications in congenitally-infected infants, and Guillain-Barré Syndrome in some infected adults. In 2016, the mosquito-borne virus continued its northern spread
into Puerto Rico as well as some US states.
In November of last year, the World Health Organization’s (WHO) Director-General, Margaret Chan, MD, MPH announced
that Zika is no longer a Public Health Emergency of International Concern. While this may be, she did stress that the virus “remains a significant enduring public health challenge requiring intense action.”
Now, on May 11, 2017, the Ministry of Health of Brazil declared
that the Zika National Public Health Emergency (NPHE) may be over.
According to the WHO International Health Regulations, in order to lift an NPHE status, four criteria need to be considered:
- What is the impact of an event on public health?
- Is the event unusual or unexpected?
- Is there a risk of international spread?
- Is there a significant risk of international travel or trade restrictions?
A news release
from the Ministry points out that now, Brazil has seen a drop of 95% in new Zika cases, compared with the same time last year. “Therefore, Brazil no longer meets the criteria of a health emergency.” In 2016, Brazil had reported more than 170,500 Zika cases, while this year, the number of reported cases has dropped to just under 8,000, accounting for a drop from 82.8 cases per 100,000 people to just 3.8 cases. In addition, a total of 293 of 1,079 probable Zika cases have been confirmed, either through “clinical-epidemiological or laboratory criteria.”
The Ministry of Health informed WHO of its decision to lift the status through a risk assessment report that was “published 18 months after the emergency status was declared.” In the time between declaring emergency status and lifting it, Brazil had expended all efforts to control the Aedes aegypti
population, a population of mosquitoes that transmit Zika, as well as other viruses endemic in the region.
However, Zika isn’t the only mosquito-borne virus in Brazil that has decreased in incidence this year. The Ministry of Health reports a drop of 90.3% in the number of new Dengue cases, and a drop of 96.6% in associated deaths. In April 2016, the Ministry saw 1,180,472 probable Dengue cases reported for that year, whereas the number of probable cases reported in April 2017 was 113,381. Deaths have also gone down from 507 in 2016 to only 17 in 2017. The number of reported Chikungunya cases has also decreased drastically, as has the number of related deaths within the country.
The Ministry of Health ensures that it will continue its vector control efforts as well as “provide assistance to infants and mothers.” In fact, the Secretary for Health Surveillance, Adeílson Cavalcante said in the news release, “Lifting the emergency status does not mean ending assistance or surveillance. The Health Ministry and other organizations operating in this area will maintain their policies regarding Zika, dengue and chikungunya, including at state and municipal level.”
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