Monday, April 27, 2009
What's New With Swine Flu?
So what is the latest word on what may be a potential pandemic ? The following give varied answers. Questions to be answered include is this the same virus in every country?, Is this susceptible to commonly used anti-virals?, And how bad may it get?
First its not clear if this has the same virulence or killing potential everywhere. The death rate in Mexico seems to be substantially higher than other countries and why this is so is not clear given the fact that so far this seems to be the same virus in the U.S. as Mexico.
Anecdotal reports from Mexico suggest that this disease is not as susceptible to commonly used anti-virals . The BBC has a number of concerning reports such as this:
"I'm a specialist doctor in respiratory diseases and intensive care at the Mexican National Institute of Health. There is a severe emergency over the swine flu here. More and more patients are being admitted to the intensive care unit. Despite the heroic efforts of all staff (doctors, nurses, specialists, etc) patients continue to inevitably die. The truth is that anti-viral treatments and vaccines are not expected to have any effect, even at high doses. It is a great fear among the staff. The infection risk is very high among the doctors and health staff.
There is a sense of chaos in the other hospitals and we do not know what to do. Staff are starting to leave and many are opting to retire or apply for holidays. The truth is that mortality is even higher than what is being reported by the authorities, at least in the hospital where I work it. It is killing three to four patients daily, and it has been going on for more than three weeks. It is a shame and there is great fear here. Increasingly younger patients aged 20 to 30 years are dying before our helpless eyes and there is great sadness among health professionals here.
Antonio Chavez, Mexico City "
As to the last question who knows? The unpredictability of these outbreaks makes prognostication difficult. CIDRAP sums it up:
" Unpredictability stressed
Schuchat stressed the unpredictability and fluidity of the swine flu situation. "We do think this virus is spreading from person to person, and we're taking steps aggressively to try to slow the spread," she said. "We are expecting things to change, and we want you to expect change as well."
In response to questions, she said it is "premature" to conclude that the disease in Mexico is different from the one in the United States, even though Mexico has had a number of deaths. "We don't have many infected people, and we don't have great information yet," she said. Though the United States has had no deaths attributed to the virus yet, "I do fear that we will have deaths here," she added.
In response to a question, Schuchat said the CDC believes that "person to person to person" (tertiary) transmission is going on. But the agency has not yet estimated how many additional cases can be expected to result from each case.
She said some of the US cases have involved US residents who traveled to Mexico, but she wasn't sure how many. The two case-patients in Kansas are a married couple, one of whom got sick after a trip to Mexico, and the spouse became ill 2 days later.
In reiterating CDC advice about self-protective steps people can take, Schuchat said, "If you're having symptoms after a trip to Mexico, that's a good time to go to the doctor and get tested." Symptoms that may suggest swine flu include a high fever, muscle aches, cough, sore throat, and possibly vomiting and diarrhea—though these could indicate many other possibilities as well, she noted.
She repeated earlier CDC assessments that the H1N1 strain in the seasonal flu vaccine is unlikely to offer protection against the new swine H1N1 strain. From the latest tests, "it doesn't look like there are cross-reacting antibodies from seasonal H1N1 to this particular strain," she said.
Commenting on the age distribution of swine flu cases, Schuchat said US patients range from about 7 years to 54 years. In Mexico, "What we know so far is that many of the patients are in their 20s, 30s, and 40s, but we're still lining up information about which have an illness actually caused by this virus." Tests have shown that some of the sick people in Mexico actually had a seasonal flu virus, she said.
Though it appears there have been few if any swine flu cases in older people, "It's really too soon for us to conclude that older persons are spared," Schuchat said.
Elsewhere, two Canadian provinces today reported a total of 6 confirmed swine flu cases, according to reports from Canwest News Service and Reuters. Nova Scotia health officials said that 2 of its 4 confirmed cases were students attending the same private school who recently visited Mexico. Robert Strang, Nova Scotia's chief public health officer, said the patients' illnesses were mild.
In British Columbia, a spokesman for the province's Centre for Disease Control told Reuters today that officials have confirmed 2 cases.
Israel's health ministry today reported its first swine flu case, in a man who had recently traveled to Mexico and returned with influenza symptoms, Kuwait News Agency (KUNA) reported. He is hospitalized and is in isolation, the report said.
According to media reports, health authorities in several countries, including France, Spain, and New Zealand, are testing several travelers who reported flu-like symptoms after traveling to Mexico.
Mexican officials have closed schools through May 6, though many schools were closed anyway during the lead-up to the Cinco de Mayo holiday. The US Embassy in Mexico City has suspended all visa and nonessential citizen services from Apr 27 until Apr 30 as a precautionary measure to protect clients and staff, according to an Apr 25 State Department warden message. "
My favorite resources include CIDRAP, PROMED and of course the CDC.