North Carolina Outdoor Workers -and surrounding states

The actual title of this article is: "Incident Tick-Borne Infections in a Cohort of North Carolina Outdoor Workers"

**I think it's totally bizarre that they didn't treat these people, but at least we have this information now!

" Abstract

Tick-borne diseases cause substantial morbidity throughout the United States, and North Carolina has a high incidence of spotted fever rickettsioses and ehrlichiosis, with sporadic cases of Lyme disease. The occupational risk of tick-borne infections among outdoor workers is high, particularly those working on publicly managed lands.

This study identified incident tick-borne infections and examined seroconversion risk factors among a cohort of North Carolina outdoor workers. Workers from the North Carolina State Divisions of Forestry, Parks and Recreation, and Wildlife (n = 159) were followed for 2 years in a randomized controlled trial evaluating the effectiveness of long-lasting permethrin-impregnated clothing.

Antibody titers against Rickettsia parkeri, Rickettsia rickettsii, "Rickettsia amblyommii," and Ehrlichia chaffeensis were measured at baseline (n = 130), after 1 year (n = 82), and after 2 years (n = 73). Titers against Borrelia burgdorferi were measured at baseline and after 2 years (n = 90). Baseline seroprevalence, defined as indirect immunofluorescence antibody titers of 1/128 or greater, was R. parkeri (24%), R. rickettsii (19%), "R. amblyommii" (12%), and E. chaffeensis (4%). Incident infection was defined as a fourfold increase in titer over a 1-year period.

There were 40 total seroconversions to at least one pathogen, including R. parkeri (n = 19), "R. amblyommii" (n = 14), R. rickettsii (n = 9), and E. chaffeensis (n = 8). There were no subjects whose sera were reactive to B. burgdorferi C6 antigen. Thirty-eight of the 40 incident infections were subclinical. The overall risk of infection by any pathogen during the study period was 0.26, and the risk among the NC Division of Forest Resources workers was 1.73 times that of workers in other divisions (95% confidence interval [CI]: 1.02, 2.92). The risk of infection was lower in subjects wearing permethrin-impregnated clothing, but not significantly (risk ratio = 0.81; 95% CI: 0.47, 1.39).

In summary, outdoor workers in North Carolina are at high risk of incident tick-borne infections, most of which appear to be asymptomatic.


doi.org/10.1089/vbz.2015.1887

Another note from me - I sure wouldn't count on being asymptomatic for the rest of one's life!! I had asymptomatic infections and it lasted a whole year, and now I'm back in treatment because those infections are no longer asymptomatic. If you or someone you know is testing positive, I encourage you to seek out treatment.

Well the comforting news is that it's likely pretty bad all over the US. I came across a report (from 1996!!) that said,

" Although Lyme disease cases have been reported from southern states, some researchers doubt the presence of B. burgdorferi or of human Lyme disease in the south. However, new data show that B. burgdorferi is widely distributed in the south and that strains are genetically more varied than in the north. Moreover, B. burgdorferi enzootic cycles appear to be more complex and more tick species are identified as vectors of the spirochete in the southern states."

www.ncbi.nlm.nih.gov/pubmed/8973401

So stock up on permethrin, and do all those things you need to do for lawns and be sure to do your tick checks!

Just a hypothesis from me but I don't know if lymes and co are becoming more prevalent or if it is just that we are getting more awareness and people are recognizing it more often so it seems as though there are more cases of it?