OFFERyme disease is first name nearly 50 years ago in Lyme, Connecticut, but tick-borne diseases are now found around the world. A new study published in BMJ Global Health It is estimated that 14.5% of the world’s population at some point has been infected with Lyme disease, which can cause short-term symptom including skin rashes, fever, headaches and fatigue – as well as long-term illnesses, including damage to the joints, heart and nervous system.
Disasters also appear increasingly serious. Lyme infection rates doubled between 2010 and 2021, compared with 2001 to 2010.
The study, led by a team of researchers from the Institute of Tropical Medicine at Kunming Medical University, China, is a meta-analysis of 89 studies dating from 1984 to 2021. The cache of those papers included blood samples from nearly 160,000 people. who was tested Borrelia burgdorferi, spiral-shaped bacteria that cause Lyme disease. Blood samples are tested using any of several methods, including ELISA test, which uses enzymes to detect the presence of antibodies in the blood; and IF ONE The test uses fluorescence to do the same job. Considered to be more reliable than both techniques are Western blotting method, which looks for proteins in the blood as markers of a target bacterial or viral infection. Western blotting is said to reduce the rate of false-positive results, but it has one major drawback: it is less sensitive in the early stages of Lyme infection than ELISA or IFA. Of the 89 studies selected, 58 used Western blotting.
Almost 15% of people worldwide have had Lyme disease which is remarkable. “[Lyme disease] The researchers wrote. “Preventive measures are needed, which requires understanding the dynamics of tick-borne disease transmission and the lack of effective disease prevention strategies.”
As for why Lyme rates have doubled in the past decade, climate change is thought to play a leading role. Higher temperatures, springs and longer summers increase ticks’ range and the amount of time people spend outside. “Ticket populations” have expanded globally and geographically in recent years, thereby significantly increasing the risk of exposure in humans, the researchers write. ”
Geography is key to determining who is most at risk for Lyme disease. The highest rates of infection are found in Central Europe, with 21% of the population affected; East Asia is second with 16%, followed by Western Europe with 13.5%. Lower risk regions are Oceania at 5.5%, South Asia at 3% and the Caribbean at 2%. The Americas ended somewhere in the middle with 9.4%. Part of the reason for the discrepancy is the varying presence of ticks that carry Lyme in different parts of the world, but other factors play a role in who is likely to get the disease and who isn’t.
People 50 years of age and older are at higher risk than younger groups. Of those who tested positive in the study, 18.1% were in this age group, compared with 17.6% in the 40-49 group and 9.5% in the 39-year-old group and younger. The researchers did not speculate on the reasons for this finding, but a weaker immune system may play a role, or merely the fact that older people have had years of exposure to the virus. Lyme than young people.
Unsurprisingly, people living in rural areas are at a higher risk than those living in urban areas, with 12.6% of positive test results coming from rural residents compared with 8.1% in rural areas. townsman. The researchers did not analyze their data by occupation, but they speculate that high-risk jobs include farmers, soldiers and housewives, all of whom may be more exposed to outdoors and tick-carrying animals such as dogs and sheep.
The different methods used to test for Lyme infection somewhat obscure the results, with Western permeability tests often giving lower overall numbers. For example, the top 14.5% is the average of the 9.8% confirmed with Western blot and 17.5% by ELISA and IFA. There is a similarly wide range when it comes to age, with ELISA and IFA showing an 18% rate in the 50 and older group compared to just 8.8% in Western blot. The researchers point to newer molecular diagnostic techniques, which are still in development, as potential ways to test Lyme more reliably and reduce such statistical ambiguity in the future.
Other must-read stories from TIME