GUANGZHOU -- South China's Guangdong province reported two new Zika cases Friday, bringing the total number of imported infections in the province to 10.

Two sisters aged 12 and 13 tested positive for the Zika virus Tuesday in Enping city, the provincial health and family planning commission said.

The two returned from Venezuela on March 23 and developed a skin rash. The younger sister has since tested negative for the virus and is under observation at home, while the elder sister is in hospital with a normal body temperature.

All eight other imported Zika cases in Guangdong have been discharged from hospital after recovery.

The World Health Organization (WHO) declared a global emergency in early February amid a Zika outbreak in Central and South America. China has also been on alert as the warming weather may facilitate the spread of the mosquito-borne virus.

Symptoms of Zika infections include fever, joint pain, rash, conjunctivitis, headache and muscle pain. It is also a suspected cause of microcephaly in new-born babies.