Germany has recorded its first case where the Zika virus was transmitted on its territory, according to one of the country's leading public health institutes Friday, a case in which a woman contracted the disease during sex.
The woman in question had sex with a partner who had picked up the disease while in Puerto Rico, reported the Robert Koch Institute. Because of the patient's geographical location and the time of the year, the institute says it can rule out that the disease was spread by mosquito, the most common transmission method.
The institute would not say where in Germany the woman lives. The woman's partner had been in Puerto Rico in April. Similar cases have been seen across Europe.
"We assumed, that sooner or later there would be a transmission," said Christina Frank of the institute's infectious epidemiology unit. She said the odds of sexual transmission are much higher in Germany than transmission via mosquito.
She said it would be impossible to rule out such cases in the future.
However, she noted that this does not make it impossible for people to protect themselves.
She noted people returning from areas at high risk for Zika should refrain from unprotected sex with pregnant women for half a year after their return. Those at risk of Zika who are in a relationship with a non-pregnant woman should restrict themselves to protected sex for a month after returning to Germany and other areas not prone to Zika, advises the World Health Organization.
The institute has recorded 49 cases in which people infected abroad brought Zika back to Germany. The case announced Friday marks the first time that the disease was transmitted on German territory.
The woman had not travelled to any areas with a high risk of Zika.
Much remains unknown about Zika, which has prompted many of the worries surrounding it. One of the main concerns is that, when pregnant woman become infected, their children can be born with microencephaly, a condition where the head and brain are significantly smaller than normal.
Although mosquitoes normally carry the disease, there is a brief window during the infection where a carrier can pass on the disease sexually, says Regine Heilbronn, head of the institute for virology at Berlin's Charite hospital.