The Israeli Health Ministry on Thursday urged the public to get the annual influenza vaccination, after a woman died and 16 others were hospitalized and quarantined over what appears to be a new swine flu outbreak. Of the 16 people hospitalized, 11 are said to be in serious condition. Two of the patients are pregnant women. A third pregnant woman diagnosed with the virus underwent an emergency caesarean section Thursday after her condition deteriorated. Her baby is said to be well, while she remains in serious condition. Swine flu, also known as the H1N1 virus, is a highly contagious strain of the influenza virus. While it initially causes regular flu-like symptoms, such as fever, coughing, a sore throat and congestion, left undiagnosed it could lead to serious complications, respiratory failure and even death. Professor Itamar Grotto, head of the Public Health Department at the Health Ministry, sought to calm the public, telling Israel Hayom, "While we still expect to see some serious cases, so far the extent of the disease is not unusual compared to previous years. It seems that the H1N1 virus is the leading cause of the disease this year. Some years see more violent outbreaks than others. We can't predict them." Grotto said that hospitals and healthcare services providers still have enough flu vaccines. "Getting vaccinated is still relevant and very important, because this is only the beginning of flu season," he said. "Unfortunately, it's only when there are [media] reports of complications that people get their flu shots. Another important thing to remember is, don't go to work if you're sick, so you don't infect others." Esther Aryeh, 55, a mother of six from the southern town of Netivot, died on Tuesday of complications related to swine flu. Aryeh had been hospitalized at the Soroka Medical Center in Beersheba for several weeks. She was transferred to the Rabin Medical Center in Petach Tikva last week after her condition worsened and she developed pneumonia. Her condition continued to deteriorate rapidly despite doctors' efforts. Dr. Philip Biderman, head of the Cardiac Intensive Care Unit at the Rabin Medical Center, stressed that Aryeh's condition was aggravated by other, pre-existing health issues. Professor Yaniv Almog, of Soroka's Intensive Care Unit, said that "swine flu complications usually lead to pneumonia or severe pulmonary injury, which hinders your ability to breathe on your own." Dr. Lior Nesher, an infectious disease specialist at Soroka, noted that "over the past few weeks we have been seeing a steady rise in flu cases, and especially swine flu cases. There's an increase of a few dozen percents in swine flu cases compared to December 2014, and the majority of patients had not been vaccinated." According to Israel Hayom's sources, health care service providers have about 300,000 flu vaccines available.