HANOI, July 27 (Reuters) - A potentially deadly pig bacteria infected four more people in northern Vietnam this week, bringing the number of humans affected to 46 this year, state media reported on Friday.

The four were taken to a Hanoi hospital on Thursday with high fever, headache and vomiting. Tests showed they had meningitis caused by the streptococcus suis bacteria, the Nhan Dan (People) newspaper quoted doctors as saying.

They said the sickest patient had eaten pig blood pudding, a popular dish in rural areas despite its high bacterial content.

Doctors say the bacterium, which has killed two people this year, can be transmitted to humans by touch, in meat or via air-borne particles.

It can cause rapid internal haemorrhaging and high fever leading to meningitis, septicaemia and swelling of the heart valves.

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