Where are we from a vaccine against Lyme disease?



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A vaccine to prevent infection with Lyme disease was briefly available in the 1990s.

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Taking precautions before hiking and doing a tick check after returning home can help prevent Lyme disease. Getty Images

According to the Centers for Disease Control and Prevention (CDC), Lyme disease is now the vector-borne infection (transmitted by insects) to the fastest growing, and it is difficult to Prevent the spread of the disease from spreading.

In fact, in 2017, the confirmed number of cases of Lyme disease was more than 29,000, an increase of 13% over 2016. Another 13,000 were probable cases of infection.

Compare that to the previous decade, in 2006, when nearly 20,000 cases of the disease had been confirmed.

Lyme disease is contracted by humans through tick bites and tick populations are booming.

The same goes for the number of cases of Lyme disease and the incidence of other tick-borne diseases.

Researchers know how to prevent Lyme disease infection: Avoid ticks that transmit the disease.

Pet owners can protect their pets with flea and tick collars and medications. In the United States, vaccines are approved for use in dogs and horses.

But for people, avoiding ticks is a bit more difficult. You can wear clothes treated with permethrin insecticide. But a human vaccine against Lyme disease is not found.

The researchers are trying to change that with a new potential vaccine being tested.

Tick ​​populations show no sign of contraction and the spread of tick-borne diseases will likely continue to increase, so that a vaccine against Lyme disease could be a big deal.

Wendy Adams, director of research grants at the Bay Area Lyme Foundation, said the actual number of cases of Lyme disease is probably much higher than the number reported.

"Due to reporting requirements, only about 30,000 cases have been reported to health authorities, which the CDC has recognized as probably representing less than 10% of actual cases," Adams said. "There is 329,000 or several new cases of Lyme Disease diagnosed each year in the United States. "

This places new cases of Lyme disease on top of most other notifiable infectious diseases, including HIV and AIDS.

"Different groups suggest that the global market for a Lyme disease vaccine is estimated at about $ 1 billion a year, based on current estimates of the cost of treating patients with acute Lyme disease and more chronic, "said Mark Wooten, PhD, professor of medicine. Microbiology and Immunology at the Faculty of Medicine and Life Sciences of the University of Toledo.

With this in mind, in 2017, the Food and Drug Administration approved a Expressway designation of a new vaccine against Lyme disease.

The Lyme disease vaccine, VLA15, from the French company Valneva, completed the first trials in early 2018 and is currently in phase II clinical trials, said Thomas Lingelbach, CEO of the company.

"With the results of two phase II clinical studies [projected in mid-2020]We expect that we have determined the optimal dosage level and timing of use for the VLA15 Phase III efficacy tests, "said Lingelbach. He added that the vaccine would still be available in four or five years.

"It's important to remember that vaccine development is measured in years. It will take some time before the vaccine reaches the general public, "said Dr. Amesh A. Adalja, Senior Researcher at Johns Hopkins. Health Security Center. "He looks promising and is the leading vaccine candidate."

While researchers are working hard to develop a new Lyme disease vaccine, many Americans may be surprised to learn that 20 years ago, a vaccine against Lyme disease was available in this area. country – and it worked.

"The LYMErix vaccine was developed by SmithKline Beecham [now GlaxoSmithKline] and licensed in the 1990s, "said Meghan May, PhD, associate professor of microbiology and infectious diseases at the College of Osteopathic Medicine at the University of New England in Biddeford, Maine.

While the vaccine was designed as a three-dose drug, research showed that the vaccine was effective in preventing Lyme disease from 49 to 68% in two injections. After the third and last injection, this number increased from 76 to 92%.

Despite this success, LYMErix did not last long. In fact, he was withdrawn from the market only a few years after his introduction, fearing side effects and subsequent lawsuits.

Shortly after LYMErix was available to consumers in the 1990s, it fell under the suspicion of suspicion.

Reports revealed that some patients who received the Lyme vaccine had developed arthritis. The media have also read this information and warned consumers, even if there is a lack of research or verified evidence, that there may be a link.

"In the space of a year, reports have suggested that a small number of people vaccinated had side effects," said May.

In 1999, 121 people who received the vaccine and developed arthritis filed a class action against the drug company. They claimed that the vaccine had harmful side effects and that the pharmaceutical company was concealing the evidence.

At about the same time, an infamous study in The Lancet newspaper linked another type of vaccine to autism. This study on autism has since been proven false and retracted, but it helped fuel an anti-vaccine movement.

Media reports on the vaccine against Lyme disease have added to the hesitation, and people have started to avoid LYMErix.

In April 2002, the company announced that sales of LYMErix had dropped from 1.5 million doses in 1999 to about 10,000 expected this year. This was despite cases of increasing Lyme disease. The company stopped producing and selling the vaccine that year.

"Unfortunately, the vaccine has garnered much negative public and media attention," said Dr. Alexea M. Gaffney-Adams, a certified physician in the field of infectious diseases, internal medicine and pediatrics at Stony Brook Medicine.

After the company withdrew the vaccine, the FDA conducted several additional tests to verify or refute the claims of the prosecution. He has not been able to reproduce the adverse events and adverse reactions reported by vaccine opponents in the trial and elsewhere.

"The company settled the class action on the basis of economic concerns for a product with poor market performance," said Gaffney-Adams.

"The final agreement included $ 1 million in legal fees, but did not provide for any financial compensation for the alleged victims of the vaccine."

Although LYMErix is ​​still approved and licensed in the US and studies are available to disprove claims of side effects, GlaxoSmithKline has never reintroduced LYMErix.

Lyme disease, which is caused by Borrelia burgdorferi bacterium, is a disease transmitted by ticks. It does not circulate in the blood, unlike many bacterial infections.

Instead, it hides in the tissues of your body. This makes it harder to detect and harder to treat.

If an infected tick bites you, you can begin to show signs of Lyme disease within one to four weeks.

"Primary Lyme Disease is what most of us know," said May. "Symptoms include fever, fatigue, pain in the body and joints and, in some cases, the characteristic rash of" bull's eye "where red rings appear around the tick bite site."

If caught early, Lyme disease can be treated with antibiotics.

If it is not caught, untreated Lyme disease can progress and become a little more serious.

"Secondary Lyme disease can include swollen or painful joints, extreme tiredness, numbness, headache, muscle weakness, conjunctivitis, poor memory, confusion and heart palpitations," said May.

If still not diagnosed at this stage, the bacteria could invade the central nervous symptom and cause problems, such as changes in mental status and effects on mood, sleep and memory, said May.

"Loss of muscle control, [muscle] tics, lack of coordination and potentially life-threatening heart complications "are also possible, she added.

Today, according to the CDC, 90% of Lyme disease cases are reported in only 14 states. The majority of these states are in the central Atlantic region (Pennsylvania and New Jersey first) and New England.

This does not mean that other states do not have ticks infected with Lyme disease.

Ticks thrive in hot weather and in spring and summer. In warmer climates, the tick season can extend until the fall and even the winter.

This is a problem because tick populations are increasing and warmer temperatures prolong the active life of ticks.

"One thing is very clear: we can reduce or avoid these complications by preventing infections, for example with a vaccine or by preventing tick bites, or by ensuring that patients are treated as early and as aggressively as possible. Said May.

In the fight against Lyme disease, treatment and prevention go hand in hand, while scientists are looking for ways to stop the slow progression of cases and prevent long-term complications.

While cases of Lyme disease increase in the United States, researchers are studying a potential vaccine to prevent tick-borne disease.

Currently, this vaccine is in Phase II testing and may be available in a few years.

But it would actually be the second Lyme vaccine published in the United States.

The original vaccine, dubbed LYMErix, was introduced in the late 1990s before being withdrawn because of side effect claims.

Although these side effects were not replicated by the FDA, the company stopped producing the vaccine in 2002.

This article was updated after being published on May 22, 2018.

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