“Many unknowns” continue to accompany the spread of the virus linked to neurological birth defects and Guillain Barre syndrome, while new questions surround funding for research, responses and the collateral damage of delays
In Brazil, where the link between the Zika virus and babies born with microcephaly to women who had been infected during pregnancy was first noted two years ago, 2,100 cases of infants born with brain damage caused by the virus have been confirmed. With 3,000 more suspected cases of Zika-caused brain damage among newborns being investigated in that country, and about a third of all such investigated cases leading to confirmation, health officials expect another thousand cases to be recorded soon. And while reported Zika infections have ebbed slightly with the passing of mosquito seasons in Brazil, the problem is far from over with from 150 to 200 cases of microcephaly identified each week.
Brazil is just one of 28 countries that have now reported cases of infants born with microcephaly to Zika affected mothers, as of last week, while 19 have reported cases of the Guillain-Barré syndrome, linked to the mosquito-borne virus. And those are just the currently known impacts of the virus that continues to spread around the globe. A study reported this week in the U.S. Centers for Disease Control and Prevention’s weekly report tells of 13 infants affected by Zika whose heads measured within the normal range at birth, but whose head growth slowed to the point that upon follow-up examinations were found to have microcephaly and indications of neurological damage. The findings highlight the need for additional information to describe the spectrum of impacts associated with congenital Zika infection, the report notes.
Welcome to the new normal for a virus that upon landing in the Western hemisphere emerged from obscurity to raise questions about links to devastating birth defects among exposed infants and paralysis among exposed adults. It was those questions, now answered, WHO officials say, that prompted the agency to declare the spread of the virus and its associated impacts a Public Health Emergency of International Concern. It is a status reached by only four disease outbreaks — the swine flu pandemic in 2009, the resurgence of polio in 2014, the outbreak of Ebola in West Africa in 2014, and then Zika, last February. The emergency of Ebola was declared ended in March 2016, although sporadic transmission, from re-emerging disease, and sexual transmission, have continued. Zika, on the other hand, will continue to spread widely, where ever a mosquito capable of transmitting it is found, in addition to being transmitted sexually as well. But with the link between the virus and neurological damage confirmed, they said, the virus constitutes an “enduring public health threat” for which there are (still) “many unknowns.”
Those unknowns include the capacity of countries with fewer resources than Brazil to track the spread of the virus, to detect its impacts, to respond to the needs that those impacts make obvious, including to provide adequate diagnostic services, reproductive health services, prenatal care, and, potentially lifelong care for affected infants. Unknowns also include the lineage of a virus that went nearly unnoticed for more than six decades, before traveling across an increasingly close-knit world and confirming its potential for harm in the most vulnerable communities in this hemisphere. And, of course, questions include how to develop the tools needed — diagnostic, programmatic and preventive — to end the threat the virus poses.
Those questions in turn, are likely to come down to whether or not the world is ready and willing to pay for the work that needs to be done as Zika joins the ranks of tuberculosis, HIV, and other diseases that have thrived especially where access to health care has not. The week after the World Health Organization declared the end of the emergency of Zika, spokespeople there said that the needed support must come from funders concerned with international development, and who are in it for the long haul, and who are willing to invest the resources that research, development, health system strengthening and the needs of those children already affected, will require.
For more on WHO recommendations, and the agency’s Zika Research Agenda, see the updated IDSA Global Health’s Zika paper.