Mar 8, 2012 (CIDRAP News) – Another family member linked to a fatal flu cluster in Calvert County, Md., has been hospitalized, as suspicion grew that an aggressive drug-resistant form of pneumonia may have played a role in the severe illnesses, according to media reports.
Maryland and Calvert County health officials didn't report any new details about the cases, but the Washington Post reported yesterday that the sister of the 81-year-old woman who died has been hospitalized at MedStar Washington Hospital Center with fever but no other flu symptoms.
Yesterday the Maryland Department of Health and Mental Hygiene (MDHMH) said seasonal H3N2 influenza had been confirmed in two of the four initial illnesses, which involved the older woman and three of her adult children, two of whom died on Mar 5 after caring for their mother. The second daughter who cared for the woman is recovering at the same Washington, DC, hospital.
Hospital officials have said the patients' influenza infections were complicated by co-infections with Staphylococcus aureus pneumonia prior to hospitalization, and Calvert County Health Officer David Rogers, MD, told the Post yesterday that the staph infections probably involve methicillin-resistant S aureus (MRSA).
Rogers also told the Post that the mother had been vaccinated against seasonal flu but that the children who cared for her had not.
Tom Skinner, a spokesman for the US Centers for Disease Control and Prevention (CDC), said the CDC was expecting autopsy samples from Maryland to arrive today, and the agency hopes to confirm what pathogens were involved within a few days, according to a USA Today report.
Secondary S aureus pneumonia is a potentially fatal complication of influenza, and one of the hallmarks can be severe necrotizing pneumonia, according to a report on 10 MRSA pneumonia cases, six of them fatal, reported to the CDC from Louisiana and Georgia during a 2-month span in the 2006-07 flu season. The report was published in the Apr 13, 2007, issue of Morbidity and Mortality Weekly Report (MMWR). The patients included both children and adults, and many were previously healthy.
The report details a short interval between respiratory symptom onset and death or isolation of MRSA from the patient. In four of the six fatal cases the patients died within 4 days of symptom onset, which the authors said suggests concomitant flu and MRSA infections, rather than a two-phase pattern seen with other types of flu and pneumonia.
Calvert Memorial Hospital, which originally treated some of the patients, said today that it has fielded a number of calls from worried area residents. Paul Pomilla, MD, the hospital's medical director for infectious diseases, said in the statement, "We understand that many in the community are nervous about the flu after reading media reports about this family’s tragedy, but we want to reassure the public that we are not aware of any other cases of serious influenza-like illness that have a confirmed link to the original patients."
The hospital advised families to follow routine flu prevention methods and to be vaccinated against flu if they haven't been already, given the flu season's late start. Hospital officials said they would continue to monitor flu-like illness patterns seen in the emergency department, urgent care centers, and hospital.
Mar 7 Washington Post story
Mar 8 USA Today story
Mar 8 Calvert Memorial Hospital statement
Apr 13, 2007, MMWR report