* 108 suspected cases in Colombia
* Ecuador tightens border with Colombia
(adds minister remarks, Ecuador controls)
BOGOTA, May 3 (Reuters) - Colombia on Sunday reported its first confirmed H1N1 flu virus case, a man who recently returned from Mexico but who remains in good condition at home after tests conducted in the United States came back positive.
Colombia's Social Protection Minister Diego Palacio said only one of 18 samples sent to Atlanta for confirmation had tested positive, although Colombia now had 108 suspected cases of the virus, which has spread around the world.
"This patient who has been diagnosed, who has tested positive, will be the first of a number of Colombians who will be affected by this virus," Palacio said at a Bogota military club where the government has set up its response center.
The man, 42, is at home in Cundinamarca Department, a province that almost surrounds the capital Bogota.
Neighboring Ecuador on Sunday said it would tighten its border with Colombia as a prevention measure. Quito already had restricted passengers from arriving on flights from Mexico to try to curb the spread of the virus.
"We've strengthened all controls on the northern frontier. The epidemiological system there ... is on maximum alert," Deputy Health Minister Marcelo Alguilar told Reuters.
Colombia already has tightened controls at its airports, ports and hospitals and Palacio said the government is working to equip local laboratories so they can confirm cases of the virus themselves.
Mexican officials said on Sunday they believe they have moved past the peak of the virus, which combines swine, avian and human flu strains and could have killed up to 100 people in the country. But world health officials warned it may still become a pandemic.
(Reporting by Patrick Markey in Bogota and Alexandra Valencia in Quito; Editing by Bill Trott)