Early Evidence Suggests Flu Season Could Be Severe This Year

17 November (Reuters Health [Megan Rauscher])—This year's infiuenza season has started earlier than it has in the past 3 years, and the infiuenza viruses circulating this year have previously been associated with more severe disease, according to the Centers for Disease Control and Prevention (CDC). One strain that is circulating is not part of the infiuenza vaccine.

All this has CDC officials “very concerned,” director Dr. Julie Gerberding said at a press briefing with reporters “This could be a worse-than-usual fiu season,” she said.

Some parts of the country—particularly Texas and Colorado—are seeing very high levels of widespread fiu infections, according to Dr. Gerberding.

This year's infiuenza vaccine for the Northern Hemisphere will protect against 3 strains: H3N2 Panama, H1N1 New Caledonia, and infiuenza B Hong Kong.

Early surveillance data suggest that a high proportion of fiu this year is of the H3N2 strain. “In some previous situations, H3N2 strains have been associated with perhaps more severe disease,” Dr. Gerberding said.

But the strain that CDC is most concerned about right now is a “drift” version of H3N2 called the Fugian strain. “It is very similar to H3N2 Panama; it's just drifted a little from the Panama strain,” Dr. Gerberding said. “Animal studies suggest that the current vaccine will provide cross-protection against this strain, but we are watching that very carefully and we will know more as the fiu season evolves,” she continued.

“It's a very common thing, as fiu strains gradually evolve in people, we don't always have exactly the same strain in the vaccine that is circulating in the community, and our experience so far historically has been that, whatever the drift is, the vaccine will still provide some cross-protection,” Dr. Gerberding said.

“We are still very early in the fiu season,” Dr. Gerberding said, and she strongly encouraged people to get vaccinated now. One “very important” group of people that need to get vaccinated now, if they haven't already, she said, is health care workers.

Editor's comment. The major points in this news item are that, this year, the infiuenza season started earlier than usual, the major infiuenza strain circulating is an H3N2 strain, and there has been an antigenic drift of this strain. I know of no significance to the earlier onset in terms of severity of infiuenza. In fact, provided that people have been immunized (usually in October or November), an earlier onset of infiuenza may yield a less severe season, because immunity wanes with time after immunization, and antibody titers may be higher with earlier outbreaks than with later outbreaks.

There has been greater morbidity and mortality during years in which H3N2 strains have been the major strains circulating. However, H3N2 strains have commonly been the major strains circulating. What is clear is that, the closer the Fugian strain is to the Panama strain in terms of antigen composition, the more protection one would expect from the vaccine. The current vaccine (both intranasal and injected formulations) should give at least some protection. It would be helpful to know just how related these strains are to each other in terms of the antibody titers against the Fugian strain achieved with the current vaccine.

CHINA BLAMES RABIES EPIDEMIC ON PET DOG FAD

25 November (Reuters Health)—Rabies cases leapt nearly 63% in China in the first 9 months of the year as the people's mad affair with pet dogs deepened, China Daily reported.

Rabies, “mad dog disease” in Chinese, killed 1297 people up to the end of September, far exceeding the 1003 deaths the Health Ministry reported for all of 2002, the newspaper said.

This is the fifth straight year that China has seen a big jump in rabies infections.

“Experts from the China Center for Disease Control and Prevention are blaming the trend in pet ownership, the shaky quality of vaccinations, the public's weak awareness of vigilance, and the low vaccination rate among the dogs as the major causes of the rapid rise in cases,” the newspaper said.

Another factor was stray dogs running wild on the outskirts of cities and in rural areas.

The ministry said earlier this year that rabies was the most deadly infectious killer in China, well surpassing SARS and AIDS.

Pet dogs were shunned in the days of Mao Zedong as a symbol of bourgeois decadence, and dog is still a popular restaurant dish. But pet pooches have become increasingly popular in the last decade with improved living standards.

Editor's comment. After all of the publicity about dogs being eaten as a delicacy in China, it is of interest to learn that they are also popular pets. It is even more striking that they are a common source of human rabies, with 11000 cases per year, compared with the rarity of cases in the United States (where they are usually of bat origin).

Usda Report: Better Security Necessary At Labs

19 November (Reuters Health)—The Department of Homeland Security should establish strict security guidelines for all government-funded US laboratories that conduct research on deadly viruses, bacteria, and chemical agents, US Department of Agriculture (USDA) investigators said.

The USDA's Office of Inspector General said it found dozens of research labs, mostly located at public universities, that were vulnerable to theft because of lax security and incomplete record-keeping.

With several federal agencies providing grants to many of the same research labs, the report recommended that the Homeland Security Department create 1 set of security rules for institutions that handle high-risk agents.

Between July and September 2002, USDA investigators visited 104 laboratories at 11 sites and found many lacking alarm systems and surveillance cameras.

In the report, the USDA said it agreed with the recommendations. It has started discussions with the Homeland Security Department on implementing a minimum security standard.

U.S. Starts Trial Of Ebola Vaccine

18 November (Reuters Health)—US researchers said they were starting testing on the first experimental vaccine against the Ebola virus in people.

The virus, which kills anywhere between 50% and 90% of victims, is still rare, but the most recent outbreak in Congo

Republic has killed at least 11 people in a remote forest region.

It is considered a threat because it is deadly, highly infectious, and has no treatment. US experts fear it could also be used as a biological weapon.

The US National Institute of Allergy and Infectious Diseases (NIAID) will test the vaccine for safety in about 2 dozen volunteers.

The vaccine, made by San Diego-based Vical, Inc., has so far fully protected monkeys from the virus. It uses pieces of DNA from the virus to prime the immune system.

“The current Ebola outbreak in the Congo provides a stark reminder of the need to rapidly develop vaccines against such perilous infections,” NIAID vaccine chief Dr. Gary Nabel said in a statement.

In the trial, 27 volunteers will get 3 injections over 2 months and will be followed for 1 year. They will not be exposed to Ebola virus. The study is meant to show the vaccine is safe.

U.S. Syphilis Rates Climb For The Second Year

20 November (Reuters Health)—Overall, the syphilis rate rose in the United States by 9.1% between 2001 and 2002, according to new statistics released by the Centers for Disease Control and Prevention (CDC).

“This represents the second consecutive increase following a decade-long decline and an all-time low in 2000,” the CDC's Dr. John Douglas said during a telebriefing with reporters.

The total number of reported syphilis cases in 2002 was 12.4% higher than in the previous year, 6862 versus 6103 cases, but since many cases of syphilis go undiagnosed, the actual number is “probably significantly higher,” he said. The overall increase—9.1%—refiects a change from

2.2 cases per 100,000 population to 2.4 per 100,000.

As in 2001, the increase in syphilis rates occurred only among men. The number of reported cases among men jumped 27.4% between 2001 and 2002. This included increases of 85.2% among white men and 35.6 percent among Latino men, while African American men experienced a slight decline of 2.6%.

Although the new statistics do not include information about sexual orientation, the CDC estimates that more than 40% of reported cases in 2002 were among men who have sex with men. “These cases account for much of the reported increase overall,” Douglas said.

In contrast to the increases among men, the new CDC data show “substantial progress” at reducing syphilis cases among women and African Americans. Syphilis cases fell 19.3% among women overall and 21.7% among black women between 2001 and 2002. Syphilis cases declined 10.3% among African Americans.

Source: MMWR Morb Mortal Wkly Rep CDC Surveill Summ 2003; 52:1117.