Mayo researchers find new Lyme disease-causing species
A team of researchers from the Mayo Clinic and state and federal health agencies have discovered a new species of Borrelia, the tick-borne bacteria that causes Lyme borreliosis, according to findings published Feb 5 in TheLancet Infectious Diseases.
The bacterium, provisionally named Borrelia mayonii, was identified in six specimens (five blood and one synovial fluid) out of 100,545 routine diagnostic samples obtained at the Mayo Clinic in Rochester, Minn., from 2003 to 2014. All six specimens that tested positive for B mayonii were taken in or after 2012.
Researchers initially observed an unusually high number of bacteria (85,000 spirochetes per milliliter) in one blood sample. Spirochetemia in patients with Lyme disease caused by Borrelia burgdorferi is typically low.
A polymerase chain reaction analysis targeting the oppA1 gene of B burgdorferi confirmed that spirochetes in the six specimens were not identical to other Borrelia species.
All six patients who tested positive for B mayonii were residents of Minnesota, Wisconsin, or North Dakota. Signs and symptoms included diffuse rash (without or in addition to erythema migrans, or the bullseye rash), nausea and vomiting, high fever, and neurologic problems with vision or speech, all of which are atypical effects of B burgdorferi.
B mayonii is likely transmitted by Ixodes scapularis (the deer or black-legged tick) and was found in ticks located near probable patient exposure sites in the Upper Midwest.
Results from the six cases suggest that infections with the new Borrelia species are detectable with available Lyme disease tests approved by the Food and Drug Administration, said the Centers for Disease Control and Prevention (CDC), which was involved in the study. In a press release, the CDC also said the patients described in the study were treated successfully with antibiotics commonly used against Lyme disease.
Lyme borreliosis is the most common tick-borne disease in the Northern Hemisphere, and B burgdorferi was previously the only bacterium responsible for causing Lyme disease in the United States.
Feb 5 Lancet Infect Dis abstract
Feb 8 CDC press release
PAHO adds almost 5,000 cases to 2015, 2016 chikungunya totals
The Pan American Health Organization (PAHO) late last week added almost 5,000 new chikungunya cases to its outbreak totals as it tallied reports from countries both this year and last.
Outbreak totals now include 3,582 new 2016 cases and 1,342 cases from 2015 as countries and territories catch up on reporting, for a combined total of 4,924 newly reported infections. Cases so far this year total 6,421; in 2015 they added up to 697,756. When combined with the 2013-14 total of 1,147,626, the more recent cases bring the overall outbreak total to 1,851,803 chikungunya infections.
Nicaragua accounted for the largest increase of 2016 cases and added all the newly logged 1,342 cases from 2015, according to PAHO's Feb 5 update. It has recorded 1,778 cases this year, all of them new. Its total for 2015 has now reached 75,404 cases, the third hardest-hit nation last year.
Colombia reported 1,292 cases, for a total of 3,178 this year. Guatemala reported its first cases of the year, 243 of them. And Venezuela added 256 cases, for 1,046 total for the year.
In the previous week, which ended Jan 29, the only country that reported new cases was Paraguay, which had 5, PAHO's Teresa Villegas Moreno told CIDRAP News.
No deaths have yet been reported for 2016. Last year saw 71 deaths, and 194 fatalities were reported in 2013 and 2014. The outbreak began in December 2013 on St. Martin in the Caribbean with the first recorded cases of chikungunya in the Americas.
Feb 5 PAHO update
PAHO 2015 chikungunya numbers
Last Ebola patient in Sierra Leone released from hospital
Sierra Leone's last remaining Ebola patient was recently discharged from a hospital, according to reports from BBC/Reuters correspondent Umaru Fofana on his social media accounts.
The 38-year-old woman was confirmed to be infected with Ebola virus on Jan 22. She contracted the virus while caring for her niece, now deceased, and the two women's illnesses ended Sierra Leone's Ebola-free status.
Fofena also said that 10 missing contacts of the 22-year-old deceased woman have been located in Kambia, in Sierra Leone's northern province. Previous reports had mentioned that authorities were struggling to locate 18 high-risk and 32 low-risk contacts.