An article in the New England Journal of Medicine (Volume 394, Issue 1, January 1, 2026) discusses congenital Zika syndrome, which causes severe brain damage in unborn babies. The Zika virus is known to usually cause only mild symptoms in adults. He describes two cases: the first patient, a 73-year-old man, was infected in southwest Mexico, where Zika is endemic, and on his return had abdominal pain, fever, eye inflammation, low blood pressure and a high heart rate. This patient was found to have an unusually high concentration of the virus in his blood, which led to his death. Genome sequencing showed that the virus was 99.8% identical to that of the mosquito from Mexico. The second patient was probably infected by accidental contact with the first patient, the first documented case of such transmission outside endemic areas. These findings help to improve the treatment of Zika as it spreads[1].