Personal protection: Treated Clothing Steve Meshnick, MD, PhD - - PowerPoint PPT Presentation

Personal protection: Treated Clothing

Steve Meshnick, MD, PhD

Professor and Associate Chair, Department of Epidemiology Professor, Department of Microbiology and Immunology

Outline

• Clothing and tick bites
• Long-lasting permethrin

impregnated (LLPI) clothing

• Future issues

Prevention of tick bites

• Proper attire

– long sleeves, tuck long pants into socks

• Repellent application onto clothing

– DEET – Permethrin

• Repellents need to be reapplied frequently

Outdoor workers and tick-borne illnesses

Location Seroprevalence against Prevalence Reference New York Borrelia 6.5% (Smith, Benach et al. 1988) UK Borrelia 25% (Guy, Bateman et al. 1989) New Jersey Borrelia 5.7% (Goldstein, Schwartz et al. 1990) Assateague Island, Maryland Borrelia 0% (Parrott, Johnson et al. 1993) New Jersey Borrelia 8.8% (1988) 18.7% (1990) (Schwartz, Goldstein et al. 1993) Italy Borrelia 23.2% (Cinco, Barbone et al. 2004) Poland Borrelia Anaplasma 41% 17.7% (Cisak, Chmielewska-Badora et al. 2005) Turkey Borrelia 10.9% (Kaya, Parlak et al. 2008) Italy Borrelia, TBE Same as controls (Di Renzi, Martini et al. 2010) Italy Rickettsia 3.9% (Cinco, Luzzati et al. 2006)

Long-lasting permethrin-impregnated (LLPI) clothing

• Predominantly marked for

protection against mosquito-borne diseases

– All US Army uniforms are impregnated

• Insect Shield treated clothing

– Effective for over 70 washes – Safe (EPA approved for all ages) – Invisible, odorless – Commercially available

Pilot Study

• Open label study of 16
• utdoor workers from

NC Division of Water Quality

• 9 wore treated

clothing

• 7 wore untreated

clothing

• One tick season

Vaughn and Meshnick, Vector Borne Zoonotic Dis, 2011.

Tick-borne Illness and Clothing Study

TICS

• Double-blinded Randomized Controlled Trial (RCT)
• Outdoor workers from the State Divisions of Forestry, Parks

and Recreation, Fish and Wildlife

TICS: Data Collection

• Annual

questionnaires

• Weekly tick logs
• Tick collection

– PCR analyses for pathogens

• Annual blood draws

– Serologies for tick- borne pathogens

Effectiveness against tick bites

N Total tick bites/total weeks Tick bites per person- week Preventive effective- ness 95% CI p-value Year 1 Control Treatment 63 64 493/1413 84/1398 0.349 0.060 0.828 0.677, 0.908 <0.001 Year 2 Control Treatment 48 53 287/1206 181†/1234 0.238 0.147 0.384

• 0.514, 0.749

0.291 Years 1 & 2 Control Treatment 64 66 780/2619 265/2632 0.298 0.101 0.662 0.341, 0.826 0.004 Vaughn et al., Am. J. Prev. Med, 2014 >90% of ticks were Lone Star ticks

Effectiveness against infection

Wallace et al., VBZD, 2016 Sero- conversion No infection Unadjusted RR (95% CI) Adjusted RR (95% CI) p-value Control 23 58 Ref Ref Treatment 17 57 0.81 (0.47, 1.39) 0.85 (0.50, 1.44) 0.54

Summary

• LLPI clothing protects against tick bites

and mosquito bites for one year

• Sample size too small to detect effect
• n incidence of infection

What about black-legged ticks?

• Evaluate protective

effectiveness against black- legged tick in Rhode Island and neighboring states

• Measure absorption of

permethrin metabolites and potential for toxicity

• Measure loss of permethrin

and bio-actvity over time under field conditions

Conclusions

• Long-lasting permethrin impregnated clothing

protects against tick bites for at least 1 year and should be recommended to those at high risk of tick-borne disease

• Better insights into factors affect durability of

protection are needed.

• Need to evaluate alternatives to permethrin

Acknowledgements

TICS

Meagan Vaughn Sheana Funkhouser Feng-Cheng Lin Jason Fine Jon Juliano Charles Apperson Logu Ponnusammy William Nicholson InsectShield CDC/NIOSH

TICS2 RI

Thomas Mathers Megan Dyer John Wallace Sheana Funkhouser Feng-Cheng Lin Stephanie Richards InsectShield CDC/NIOSH