NEW YORK • Serious complications are rare among young children infected with the Zika virus, federal health researchers have concluded in a study - a rare bright spot in the unfolding story of the epidemic.
About 160 teenagers and toddlers infected with the Zika virus have been reported to the Centres for Disease Control and Prevention (CDC) since last year. The agency's new study, published last Friday, marks the largest survey yet of laboratory-confirmed cases in children.
All of the infections were the result of travel, most commonly to the Dominican Republic and Puerto Rico. About 100 of the cases occurred in June and July alone.
The report represents just a fraction of the actual number of children in the continental United States infected with Zika.
The children, aged one month to 17 years, were initially identified because they had symptoms of infection; only those who became ill were included in the research.
Yet, most people who are infected have no symptoms at all.
The virus can profoundly injure developing foetuses, leading to a range of birth defects including irreparable brain damage, hearing loss and eye defects.
But the CDC researchers, reassuringly, found no serious injury among infected children.
Typically, these children were only mildly ill: 129 had a rash, while half were feverish, and a quarter had red eyes or joint pain.
One hundred and eleven had two or more of the four main symptoms. Five teenagers, aged 16 and 17, were pregnant when they developed symptoms, highlighting the need for sexually active teenagers to protect themselves from Zika, especially after travel to affected places.
None of these children developed a kind of temporary paralysis called Guillain-Barre syndrome, which may be triggered by Zika infection.
Older adults are generally thought to be at higher risk for Guillain-Barre. But at the height of the Zika epidemic in Brazil, officials reported that a few children had developed the paralysis, as well as meningoencephalitis, a dangerous inflammation of the brain and spinal cord.
Still, the CDC urged healthcare providers to test children with suspected Zika infection, to notify state health departments of all cases and to remain vigilant for neurological complications even in the very young.
No child died in the CDC study, but two were hospitalised. A four-year-old with a fever, a cough and trouble eating or drinking spent three days under observation. A one-year-old with a cough and rash spent a night in a hospital.
Also on Friday, the CDC announced that men who have visited areas in which the virus is circulating should wait six months before having unprotected sex in order to avoid transmitting the virus, even if they have not had symptoms.
The CDC had earlier recommended that men refrain for six months if they had experienced symptoms of Zika infection but only eight weeks if they had not. The change brings the CDC's advice in line with guidelines from the World Health Organisation.