SANAA, Yemen — In Al-Gumhouri Teaching Hospital in Sanaa, a security guard in a hallway has covered his mouth and nose with a face mask and refuses to shake hands with patrons asking his permission to visit patients in the hospital. The guard told one of the visitors, “Sorry, we are taking precautions because of the virus.”

He was referring to the swine flu virus (H1N1), which has been infecting residents of one of the poorest countries in the Middle East amid a devastating civil war that has attracted regional intervention and has been ongoing for 11 months. This new killer came on the scene in mid-January, and as of the beginning of February had killed 20 people and infected 26 others, according to statements Al-Monitor obtained from the Yemeni Ministry of Health.

Tamim al-Shami, spokesman for the Ministry of Health told Al-Monitor, “Sixteen people in the capital, Sanaa, have succumbed to the virus.” The first cases of people being infected with H1N1 were reported in 2009 in the United States and Mexico. At the time, the World Health Organization declared a state of emergency, fearing a global pandemic. Patients typically present with extremely high fevers and pneumonia.

By early February, local authorities in the oil-rich province of Hadramout, on the Arabian Sea nearly 500 miles from Sanaa, had recorded 30 cases of H1N1, four of them fatal. According to health officials, Seiyun General Hospital had treated 15 cases. The town of Seiyun lies in the middle of a desert valley some 223 miles from Hadramout's provincial capital. Authorities were asked to quickly provide treatments, protective wear and money for medical staff.