pneumonia

Sad news out of Maryland, and a reminder of how devastating MRSA, methicillin-resistant Staphylococcus aureus, can be when it combines with flu infection. According to the Maryland Department of Health and Mental Hygiene, the Washington Post and ProMED, five members of a family have fallen ill and three have died from MRSA pneumonia that took hold in lungs inflamed by flu infection.

The dead are Ruth Blake, 81, and her children Lowell, 58, and Vanessa, 56. Another child, Elaine, also fell ill and was hospitalized, and Ruth Blake’s sister has been hospitalized also. They had all contracted one of the seasonal flu strains circulating this year: H3N2. According to the Post, Ruth Blake was vaccinated against flu this season; her children were not. The assumption is that both flu and MRSA spread from the mother to the children.

 From the Post:

Calvert health officials said in a statement Wednesday that the cases were isolated to a single family and that “there are currently no other affected individuals.” Local health-care providers, they said, are not reporting any significant increase in patients with flulike symptoms.

David Rogers, the county’s health officer, said health officials suspect that Blake also had the flu and then suffered a serious lung infection that turned into pneumonia.

“In older people, that can often be fatal,” he said.

Blake had a flu shot, he said. None of the others were vaccinated.

What’s unusual, he said, is that the infection spread from the mother to three children, probably at her bedside. Most likely, the mother’s coughing spread the virulent organisms into the air, and her caregivers, two of whom also had the flu, breathed them in and became infected, he said. (Byline: Annys Shin and Lena H. Sun)

MRSA pneumonia is fast-acting and lethal; it is often called “necrotizing pneumonia” for the way it simply kills lung tissue. Exactly why it has that effect is still disputed — MRSA has so many cellular toxins at its disposal that there could be a number of culprits — but there is no dispute that it is a very serious disease.

MRSA post-flu pneumonia isn’t well-understood because it has been a concern only recently. The first cases to alert the United States this might be a problem were in Baltimore in the flu season of 2003-04. The four patients were all seen at Johns Hopkins University Medical Center, and physicians there wrote the cases up afterward. Over two months, there was a 31-year-old woman who was in the hospital for four weeks; MRSA ate holes in her lung, the largest of which was 1 by 1.5 inches. Two other women, 20 and 33 years old, were each hospitalized for three months. The 20-year-old’s heart stopped, and her blood clotting grew so disordered that doctors had to amputate one leg below her knee; the 33-year-old lost both lower legs. The fourth patient was a 52-year-old man, a two-pack-a-day smoker, who died.

Other reports came into the Centers for Disease Control and Prevention over the course of that flu season. When the CDC counted up the following summer, there had been 15 cases of severe MRSA pneumonia in 9 states. Four of them died. CDC personnel wrote another article warning of the dangers of MRSA and flu two years later, after clusters of cases in Louisiana and Georgia during the 2006-07 flu season. They said: “Secondary S. aureus pneumonia is a potentially catastrophic complication of influenza… MRSA [community-acquired pneumonia] often affects young, otherwise healthy persons and can be rapidly fatal.”

Pneumonia that follows on flu is a seriously under-appreciated danger of flu infection: An analysis from 2010 points out that, in 2007, there were 457 deaths from flu in the US and 52,847 deaths from post-flu pneumonia. There is no reliable way to protect yourself against MRSA, since there is no vaccine, and the bacterium can live on the skin undetected for an unpredictable period of time. Hypothetically, if you prevent flu infection you lessen the likelihood of this pneumonia occurring — but as the mother’s case illustrates, flu vaccine doesn’t confer perfect protection, especially not in the elderly whose immune systems are not robust enough to begin with.

It’s a very sad story, and another illustration of how perilous and destructive MRSA can be.

http://www.wired.com/wiredscience/2012/03/flu-mrsa-pneumonia/