Dr. Stafford Tick Management Handbook - Newtown, CT

StaffordThe Connecticut Agricultural Experimentation StationDuring the 1960s and 1970s, my husband, four children, and I were periodically plagued withmysterious symptoms. In time, I came to suspect that these ailments were somehow linked.Polly Murray, 1996The Widening Circle:A Lyme Disease Pioneer Tells her StoryTick-Associated DiseasesThere are at least eleven recognized human diseases associated with ticks in the United States,seven or eight of which occur in the mid-Atlantic or northeastern states. Each of the diseasesis highlighted in this section of the handbook. The greatest attention is given to Lyme disease,anaplasmosis (ehrlichiosis), and babesisois. Although each is a zoonotic vector-associated disease,not all are caused by an infectious agent or are exclusively tick transmitted. A toxin causes tickparalysis, tularemia can be transmitted through contaminated animal tissue or other materials, andbabesisois and anplasmosis can be transmitted perinatally and through blood transfusion. Tickassociations with other pathogens like Bartonella or Mycoplasma are not yet clearly de. ned. Thecausative agents transmitted to humans by the tick are maintained in a reservoir host. Ixodes tickscan be infected with more than one agent and co-transmission and infection can occur. Alternatively,multiple infections can occur from multiple tick bites. In a Connecticut and Minnesota study, 20% ofLyme disease patients also had serological evidence of exposure to another tick-borne agent.Table 2. Tick-associated diseases in the United States.Disease Pathogen or causal agent Tick VectorAnaplasmosis, granulocytic Anaplasma phagocytophilum I. scapularis, I. pacificusBabesiosis Babesia microti I. scapularis, I. pacificusColorado tick fever CTF virus (Retoviridae) D. andersoniEhrlichiosis, monocytic Ehrlichia chaffeensis A. americanumLyme disease Borrelia burgdorferi I. scapularis, I. pacificusSouthern rash illness Borrelia lonestari (?) A. americanumPowassan encephalitis Powassan virus I. cookeiRocky Mountain spotted fever Rickettsia rickettsia D. variabilis, D. andersoniTick-borne Relapsing Fever Borrelia species Ornithodoros species ticksTularemia Franciscella tularensis D. variabilis, A. americanum, othersTick paralysis Toxin D. variabilis, D. andersoniLyme disease, monocytic ehrlichiosis and granulocytic anaplasmosis, Rocky Mountain spottedfever, and tularemia are nationally reportable diseases. The amount and quality of surveillancedata provided to state health departments and then to CDC is quite variable. Most surveillanceis passive, dependent upon physician reporting. Most diseases are greatly underreported. Activesurveillance or laboratory-based reporting may also exist in some states or areas. Case reports arebased on a standardized surveillance case de. nition, which is not meant to be the basis for diagnosis.An increase in case reports can represent a true increase in disease or increased awareness of thedisease and increased reporting. Conversely, a decrease may represent a change in reporting or alack of reporting, rather than a true decrease in the incidence of disease. Nevertheless, surveillancecase reports generally provide valuable long-term tracking of disease trends and may in. uence theallocation of resources to monitor, study and prevent disease.20Bulletin No. 1010