A month after Germany made it mandatory for all the Zika cases to be reported to the government, at least 12 fresh cases of Zika emerged in May.

The German authorities had recently introduced compulsory registration for people infected with Zika. The health officials in the country are suspecting the fresh cases may be because people who travelled overseas got infected with the virus, the Xinhua reported.

The total number of Zika cases officially registered in the country is 56.

"We believe that each of these patients has been infected while traveling," a spokeswoman of the Robert Koch Institute, an organization responsible for disease control and prevention told a German Newspaper, Xinhua reported.

The health officials are apprehending that the number of Zika cases in the countries may be even more because the symptoms of the disease are often mild and hence people may not even take notice.

Zika, declared as a public health emergency by the World Health Organization (WHO), is a vector borne disease transmitted through the bite of an infected Aides mosquito. The same mosquito is responsible for the transmission of Dengue and chikungunya.

The World Health Organization (WHO) had earlier warned that Zika virus threat may be far from over and also urged the countries to allocate a substantial part of their budget to fight Zika.

Scientists have also predicted that Zika virus can transmit through sexual intercourse and blood transfusion.

In Brazil, the Zika has been suspected of causing an increase in the cases of microcephaly, which is a congenital disorder leading to abnormally small size of heads in babies.

In United States where nearly 350 Zika cases have been reported, the virus is linked to cause Guillain-Barré syndrome(GBS) – a health condition in which the patient's immune system attacks itself, resulting in muscle weakness or paralysis.