As I followed the stories on the accidental use of the 1957 H2N2 influenza strain in test kits manufactured by Meridian Bioscience Inc., I noticed that some of the headlines seemed to be worded to incite panic. The Guardian had “Labs scramble to destroy deadly flu virus”. AP headlines screamed “Countries destroying vials of deadly flu strain” and “WHO says killer flu strains still sought”. USA Today ran “Samples of pandemic flu virus found in 3 foreign warehouses of shipper”. If someone read the headlines, (deadly, killer, pandemic), without reading the articles; he or she would want to stay home and avoid all contact with the outside world.
Most people have been desensitized to panicky headlines, but it did get to some susceptible individuals. The following comments appeared on a liberal website: “has anyone entertained the notion that the vials were sent on purpose, with the intention of starting an epidemic? I mean, a few on accident is one thing, but 5,000 vials?” First, a few vials would seem more suspicious. Biological manufacturing works like any other manufacturing operation. Manufacturers make large batches or lots and then fill individual vials. How cost effective would it be if Coca-cola only manufactured enough CokeÃ’ to fill one can and repeated that process for thousands of cans? In Meridian’s case, the H2N2 influenza strain was taken from a virus “library” purchased from another company and was, apparently, unaware that it was the virus that caused the 1957 epidemic. That strain was used in one or several lots. If only a few vials contained the strain it would imply that someone retrieved material meant to be destroyed or had deliberately made those vials.
If someone were trying to start an epidemic, he or she probably would have used something more lethal. The A/Singapore H2N2 “Asian” flu strain did cause between one and four million deaths worldwide. In the US, it caused 70,000 deaths in a 1957 population of 171,984,130. That was 0.041% of the US population or 41 deaths per 100,000 people. In 2001 there was no flu epidemic in the US, but 21.8 people per 100,000 died from influenza or pneumonia from secondary infections, (the usual cause of influenza deaths). It is true that the mortality rate during the 1957 “Asian” flu was twice that of a normal year, but death tolls from other diseases are higher. In 2001, there were 245.8 deaths per 100,000 due to heart disease and 194.4 deaths per 100,000 due to cancer.
If an epidemic of the H2N2 strain of flu were to happen now, the mortality rate may be lower than it was in 1957. The 1957 “Asian” flu pandemic may have infected more people than the 1918 H1N1 “Spanish” flu pandemic did. However, the mortality rate was lower in 1957 than in 1918 because antibiotics were available to treat secondary bacterial infections. Today, we have newer drugs such as Amantadine, Rimantidine, Zanamivir (RelenzaÃ’ ) and Oseltamivir (TamifluÃ’ ) to shorten the duration of influenza infections. There is also the possibility that some older people, the most susceptible group, may have some immunity to that influenza strain because that strain circulated in humans until 1968.
Another reason it is unlikely that someone released this flu strain in hopes of starting an epidemic is that it was only sent to laboratories experienced in viral testing. Laboratories have to have appropriate certification to receive infectious agents. Laboratories are highly regulated, (often by more than one agency), controlled environments. The virus was only used under Biosafety Level 2 conditions in which laboratory access is limited to authorized personnel, appropriate safety attire is worn, waste is decontaminated and work with this type of agent is performed in biological safety cabinets. Infection of a laboratory worker is highly unlikely under these conditions. I have worked in biotechnology for 15 years and know no one who has had a laboratory acquired infection. In fact, I don’t even know anyone who knows somebody who got an infection from working in a lab. Laboratory workers don’t want to get sick any more than anyone else does. This flu strain was shipped to labs in September and no laboratory infections occurred yet. If someone wanted to start an epidemic, he or she would release an agent in an aerosol form in a crowded, public place.
Additionally, the biotechnology industry is so regulated that it is relatively easy to track and account for the virus. The H2N2 strain was detected on March 26 by a Canadian laboratory that identified influenza viruses by strain, (the strain was used as a kit control to confirm that tests were detecting influenza type A). Less than a month later, almost all of the vials of H2N2 influenza have been destroyed. Two missing shipments have been tracked to shipper’s warehouses and one shipment is still being traced. Overall, the CDC, WHO and the laboratories did a very good job of tracing and destroying the vials
Remember that agents sent to laboratories are shipped, used and disposed of under controlled conditions. Safety is a priority. Incidents like this don’t always indicate terrorism – sometimes things are accidental. Also, it’s the flu, not the plague.
Ó Eva Ellsworth, 04/20/05, all rights reserved
