Lyme Disease Vaccination

In this column we will look at a significant new development in the prevention of Lyme disease. Lyme disease is caused by an organism called Borrelia burgdorfei which is a spirochete. As discussed in a previous column, B. burgdorfei requires a tick carrier to transmit the disease to you. Please refer to the previous column for further details. Recently a vaccine was developed that targets this organism and was over 75% effective in preventing Lyme disease. This vaccine, named LYMErix is the first major development in the management of Lyme disease since the discovery of B. burgdorfei.

The first line of defense in the prevention of Lyme disease is still the use of personal protective measures. These include tucking your pant legs into your socks and using repellents such as DEET and permethrin. The most important defense is a daily full body inspection to locate and remove ticks. In the vast majority of cases transmission of Lyme disease requires 24-48 hours of tick attachment. Unfortunately, most people who develop Lyme disease do not recall a tick bite. This is where vaccination could be helpful.

The vaccine triggers your immune system to build up antibodies against Lyme disease before you are infected. Later if you are bitten by a tick carrying Lyme disease your immune system can immediately kick in and eliminate the infection before you develop symptoms. The vaccine has been very well studied over the past couple years and appears to be quite safe and very effective. In large clinical trials people from ages 15-70 were vaccinated against Lyme disease using a series of three injections over a one year period. The efficacy of the vaccination after the full series of three injections was 76% in preventing Lyme disease. Two injections was protective in only 49% of patients demonstrating the importance of receiving the complete series. At this time it is not clear if and when boosters will be required although preliminary data indicates that they will probably be necessary.

The vaccine is administered as a series of three injections over a one year time period. The second injection should be given 1 month after the initial one. Ideally the second(1 month) and third(1 year) injections should be timed to be given about 2 weeks before the beginning of tick season to allow your body to develop immunity. In most areas the second injection should be given in March or early April. The typical cost of the three injections should total about $150.00 which is less expensive than a single course of many antibiotics used to treat advanced Lyme disease.

The safety of the vaccine looks excellent. The most common reported side effect was pain at the injection site which was noted by 24% of patients. About 3% of patients developed body aches and a flu like illness which was self limited. Also some recipients developed a brief episode of arthritis which quickly resolved. By 30 days after injection there were no significant side effects.

The decision to receive Lyme disease vaccination should be based on a person's likelihood of being bitten by a tick carrying Lyme disease. This risk is influenced by the amount of ticks in your area and more importantly the percentage of ticks carrying Lyme disease. Increased tick contact because of more time in the woods increases an individual's risk. Obviously hunters, because of increased time in the woods are at higher risk. This risk is only increased in areas where Lyme disease is prevalent. Hunters in Vermont will not need vaccination whereas hunters in Connecticut and Southern NY should almost certainly be vaccinated. If you are unsure of the prevalence of Lyme disease in your area contact your physician or your state department of health. Lyme disease is a reportable disease meaning that physicians must notify the state about confirmed cases of Lyme disease. Each state keeps accurate records of Lyme disease transmission. The final decision to receive vaccination should be made in consultation with your physician after discussing the risks and benefits.

Some people should not receive the vaccine. People who are pregnant or have an immune system disorder should not be vaccinated. In large clinical trials people who have previously had Lyme disease but completely recovered had no problems with the vaccine. In contrast, patients who have treatment resistant Lyme disease with ongoing symptoms such as chronic Lyme arthritis should not be vaccinated as the vaccine could potentially worsen their symptoms. It should be noted that being vaccinated will alter the blood test used to detect Lyme disease. The test can be modified to give accurate results as long as you notify the physician that you have been vaccinated.

Lyme vaccination is an important step forward in the overall management of Lyme disease. While it is not necessary or indicated in all hunters, for those of you who live or hunt in endemic areas it can offer increased protection against a troublesome disease.