Survivors of the deadliest tsunami on record face serious water-borne diseases such as cholera, and will urgently need medicine and access to healthcare in the months ahead, doctors and health experts said on Friday.

Gandhimathi Jayaraman, a doctor with the Red Cross tending survivors in some of India’s worst-hit areas, said while clean, safe water was now available to some people displaced by the tsunami, the real test would be in the months ahead.

“Now, a lot of small relief groups are taking care of them, it’s like a honeymoon period. But when interest of the public wanes, then comes the problem,” she told Reuters by telephone.

Gandhimathi was in the tsunami-ravaged district of Nagapattinam in Tamil Nadu this week, where about 25,000 people are now housed in seven shelters. She had not seen large outbreaks of disease but said it was only a matter of time.

“When these people restart their lives, definitely, viral diseases and other diseases through water contamination will increase. Everywhere is flooded, water is contaminated, it has taken along with it, everything in its way, including sewage,” she said.

A 9.0 magnitude undersea quake off the Indonesian island of Sumatra on Sunday triggered a tsunami that slammed into Indonesia, India, Thailand, Sri Lanka, Malaysia and countries as far away as Africa, killing more that 126,000 people. Thousands of others are missing.

Many more are displaced and in India, Indonesia and Sri Lanka, survivors are most threatened by water-borne, gastrointestinal illnesses such as cholera, typhoid and hepatitis as well as infections from E. coli and salmonella, doctors say.

A growing threat is gastroenteritis, an intestinal infection caused by ingesting dirty food or water. Victims suffer diarrhoea, vomitting and dehydration, which could be fatal in the elderly and children.

CHILDREN VERY VULNERABLE

“Gastroenteritis can be rapidly fatal for children. In absolute terms, children have very little water, so when they lose water, suffer diarrhoea, they can go into irreversible shock,” said Fok Tai-fai, a paediatrician and dean of the Chinese University’s medical school in Hong Kong.

“When refugees go back home, they should have safe drinking water and proper sanitation systems. That has broken down in many places,” said Gandhimathi.

Fok called for the provision of antibiotics, which are necessary because survivors, weakened and probably malnourished, were susceptible to infections brought on by minor wounds.

He also warned of an outbreak of measles, of which there are already cases reported in Sri Lanka.

“Doctors are necessary, but without support, there is nothing a doctor can do. We need antibiotics, clean water, clothing, food, these are most important,” Fok said.

Henry Yeung of the Hong Kong Doctors’ Union warned of dengue fever in warmer places because dirty water will attract mosquitos.

“We need preventive measures, things like clothing, mosquito nets and coils,” he said.