Much has happened since our lasting posting on the Brazilian Zika outbreak (1). In particular, the major topic of our last posting was the uncertainty regarding whether Zika virus causes congenital birth defects. Recent findings may be settling the issue.
One reason for the earlier uncertainty was that although Zika virus has spread to more than a dozen countries since its discovery in Uganda more than 50 years ago, Brazil remained the world’s only country in which the virus was associated with microcephaly. However, in February 2016, Brazil’s neighbor, Colombia, now the world’s second-most Zika-affected country, reported its first cases of birth defects linked to Zika.
More direct and compelling evidence for Zika as an agent of microcephaly was reported early this March in the New England Journal of Medicine (2). Ultrasound examination of Zika-infected pregnant woman revealed that 29 percent of them carried fetuses suffering “grave outcomes, including fetal death, placental insufficiency, fetal growth restriction, and CNS injury.” Zika infection of the mothers was confirmed by reverse-transcriptase–polymerase-chain-reaction assays of blood and urine specimens. “To date, 8 of the 42 women in whom fetal ultrasonography was performed have delivered their babies, and the ultrasonographic findings have been confirmed.”
Although the above study examined only 88 women, all at one clinic in Rio de Janeiro, an article in the New York Times (March 5, 2016) quotes Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases as saying, “Now there’s almost no doubt that Zika is the cause.”
Another notable report described a case of a pregnant woman who, while living in Brazil, came down with a Zika-like feverish illness at the end of the first trimester of her pregnancy (3). The mother opted to abort her 29-week-old fetus after it showed signs (by ultrasonography) of microcephaly—subsequently confirmed by autopsy of the fetus. Importantly, a flavivirus was visualized in the fetal brain by electron microscopy, and the entire Zika genome (unambiguously identified by reverse-transcriptase–polymerase-chain-reaction assay) was recovered from it.
Next, we consider a new finding that Zika can be present in breast milk. Whereas Zika is an arthropod-borne virus that is transmitted primarily by its mosquito vector, our first posting on the Brazilian Zika outbreak noted at least one instance in which Zika was transmitted via a blood transfusion (4). In addition, there were reports of Zika being sexually transmitted (5). Now there is a report of Zika virus in the breast milk of a mother in New Caledonia (6).
The woman was feverish in July 2015 when she arrived at the hospital to give birth. Nevertheless, she breast fed her apparently healthy baby immediately after delivering it. Samples of the mother’s serum and breast milk then tested positive for Zika virus by reverse-transcriptase–polymerase-chain-reaction assay, while a test of a serum sample from the 3-day–old baby was ambiguous. The mother’s fever, now accompanied by a characteristic Zika rash, persisted for the next several days. Nonetheless, she and her baby were each healthy when they left the hospital.
This report would appear to raise considerable concern that a Zika-infected mother might transmit the virus to her baby via her breast milk. All the same, the US Centers for Disease Control and Prevention (CDC) maintains that the benefits of breastfeeding outweigh the theoretical risks of Zika virus infection via breast milk, and recommends that infected women should breastfeed.
Next, we consider some recent history. On February 1, 2016 the WHO declared that Brazil’s Zika outbreak is as an international public-health emergency. But, uncharacteristically, the WHO put forth this pronouncement despite the fact that the scientific community was still not sure of the threat that Zika poses to humans. In point of fact, this was the first instance in which the WHO proclaimed its highest level of alarm for an agent of uncertain danger. [The CDC likewise elevated its Zika virus surveillance program to its highest priority level.]
Why did the WHO make its frightening declaration when the threat posed by Zika was still not clear? Obviously, a failure to take immediate action might allow the Zika outbreak to get well out of hand, with possibly devastating consequences.
In contrast to the hurried response by the WHO to the Zika outbreak, that agency responded more leisurely to the 2013/2014 West African Ebola outbreak, which did get out of control, and which persists even to this day. So, perhaps the more urgent response of the WHO to the Zika outbreak reflects a lesson learned from the Ebola affair.
But, why did the WHO wait longer before responding to the West African Ebola outbreak? One reason is because it was strongly criticized for “overreacting” to the risk posed by the 2009 H1N1 influenza epidemic—which turned out to be far less threatening than originally feared.
While the WHO may have learned a lesson from its somewhat unhurried response to the Ebola outbreak, its more urgent February 1, 2016 Zika declaration did not go far enough for some observers, since it stopped short of advising pregnant women not to travel to Zika-affected regions. For that reason, the WHO has been accused of taking political considerations into account, to the detriment of good public health policy. Any travel ban—even one aimed only at pregnant women—would be embarrassing and costly to Brazil, which has been moving ahead with its plans to host the Olympic Games this summer. Still, hundreds of thousands of people from around the world, including female spectators and participants, some of whom may be pregnant, are expected to attend.
Lastly, we note that the Zika outbreak has been stirring up a fierce religious debate in Latin America; a debate that is actually challenging the very authority of the Catholic Church in the hemisphere. But first, an earlier posting on the blog recounted how in 2002 Colin Powell, at the time Secretary of State in the George W. Bush administration, advocated that sexually active young people should use condoms to protect themselves against HIV/AIDS (7). Powell’s advocacy of condom usage was contrary to the Bush administration’s strongly held abstinence-only approach for preventing sexual transmission of HIV. Moreover, then as now, Powell’s stance was contrary to the official position of the Catholic Church on artificial contraceptives. Nevertheless, Powell asserted, “I certainly respect the position of the Holy Father and the Catholic Church. In my own judgment, condoms are a way to prevent infection. Therefore, I not only support their use, I encourage their use among people who are sexually active and need to protect themselves.”
Now, presumably in response to reports that Zika virus might be transmitted sexually, Pope Francis declared on February 18, 2016—during a mid-air news conference on his flight from Mexico back to Rome—that contraceptives could be used to block the spread of Zika virus. That same day, the WHO advised the sexual partners of pregnant women to use condoms, or to abstain from sex, if they live in a Zika-affected area, or if they are returning from one of those areas. Also, several Latin American governments asked their female citizens to delay getting pregnant.
Those suggestions, whether from Latin American governments, or from the WHO, offended many Latin American women, in part because of the strict anti-abortion laws, and laws that restrict access to contraceptives in some of those countries. Moreover, the situation is compounded in some regions of the hemisphere by rampant sexual violence against women. In any event, the Pope’s pronouncement intensified an angry debate over contraception, and abortion as well, that was already underway in Latin America.
Pope Francis did not condone abortion, which he referred to as an “absolute evil.” But, he did make a point of justifying his statement condoning contraception by citing as a precedent a 1960 judgment by Pope Paul VI, which permitted nuns in the Belgian Congo, who were in danger of being raped, to use contraceptives.
Pope Francis’ remarks, such as “avoiding pregnancy is not an absolute evil,” has encouraged Latin American opponents of the church’s longstanding ban on the use of artificial contraceptives to campaign harder against those policies. In any case, the Pope’s pronouncement, and the heated response it is provoking, shows that the Zika outbreak is now impacting religious institutions. And, as noted by Ana Ayala, the director of the Global Health Law Program at Georgetown University, “The pope’s positioning on this subject can significantly shift how governments see access to contraception.” See Aside 1.
[Aside 1: Ayala’s comment can be found in a February 18, 2016 article in the New York Times, entitled “Francis Says Contraception Can Be Used to Slow Zika”, by Simon Romero and Jim Yardley. This piece offers an extensive account of the response in Latin America, and elsewhere, to the Pope’s comments. “While international researchers are still trying to prove definitely a link between Zika and microcephaly, the pope’s comments on contraception seemed to catch up to the reality in parts of the hemisphere where many Catholics pay little heed to the church’s teachings on birth control.”]
- Zika Virus, Part 2: The Link to Birth Defects, Is It Real?, Posted on the blog February 23, 2016.
- Brasil, P., Pereira, J.P., Gabaglia, C.J., et al., Zika Virus Infection in Pregnant Women in Rio de Janeiro — Preliminary Report, N. Engl. J. Med., March 4, 2016DOI: 10.1056/NEJMoa1602412
- Mlakar, J., Korva, M., Tul, M., et al., Zika Virus Associated with Microcephaly, N. Engl. J. Med. 2016; 374:951-958 March 10, 2016 DOI:10.1056/NEJMoa1600651
- Zika Virus: Background, Politics, and Prospects, Posted on the blog February 4, 2016.
- Foy, B.D., K. C. Kobylinski, J.L. Foy, et al., 2011. Probable Non–Vector-borne Transmission of Zika Virus, Colorado, USA, Emerg Infect Dis. 17: 880–882.6.
- Myrielle Dupont-Rouzeyrol, M., Biron, A., O’Connor, O., Huguon, E., and Descloux, E., Infectious Zika viral particles in breastmilk, The Lancet 387:1056, March 2016. doi:10.1016/S0140-6736(16)00624-3
- Colin Powell on HIV and Condoms, Posted on the blog July 30, 2014.