ABSTRACT
la pediculosis capitis humana es una infestación del cuero cabelludo y del pelo, ocasionada por el Pediculus humanus capitis, la que puede producir infecciones bacterianas secundarias en el sitio del rascado, anemia y estrés social y psicológico con alteración en la calidad de vida y consternación. Entre Marzo y Julio de 2011, se realizó un trabajo para estudiar aspectos epidemiológicos y clínicos de la pediculosis capitis en 199 personas (79 varones y 120 mujeres), habitantes de diferentes grupos etéreos (0-75 años; ? ± D.S= 21,28 ± 17) de la población rural Arenales, zona semiárida del estado Falcón, región nor-occidental de Venezuela. El diagnóstico ectoparasitológico se realizó por observación directa con peine "ad hoc" de huevos (liendres), estados imaginales y/o pre-imaginales sobre el cuero cabelludo. Los insectos se clarificaron y montaron en medio de Hoyer para observación microscópica. Los resultados revelaron una prevalencia global de pediculosis capitis del 10,10% (20/199), con porcentajes de infestación significativamente mayores en las niñas (90 vs 10%) [Odds Ratio (OR) = 3,04; p = 0,01] en edad escolar (OR= 1,02; p =0,015;) con longitudes de cabello mayores de 3 cm (OR = 2,44; p = 0,004) y de tipo lisotrico (OR = 2,25; p = 0,015), sin embargo, no fueron diferentes entre grupos étnicos y color de pelo (P > 0,05). Se detectó un predominio de liendres (65%) desde 1 hasta 64/individuos, ubicadas entre 0,1 y 9 cm del cuero cabelludo en todas las regiones de la cabeza, teniendo los individuos de menor edad las mayores cargas ectoparasitarias. Los síntomas significativamente asociados a pediculosis fueron el prurito (6,53% en individuos infestados y 12,06% en los no infestados; OR =11,99; p = 0,000) y las excoriaciones (1,51% en niños infestados y 3,52% en los no infestados; OR =4,34; p = 0,03). Otros posibles factores de riesgo significativamente involucrados en la dinámica de transmisión y mantenimiento de la infestación fueron: jugar en piso de tierra (OR = 2,20; p = 0,012) y lavarse el cabello ≥2 /semana (OR = 1,01; p = 0,002). A la luz de los resultados obtenidos, es recomendable mejorar las condiciones socio-sanitarias del sector y mantener campañas de promoción y educación para la salud.
The human pediculosis capitis is a scalp and hair infestation caused by head lice Pediculus humanus capitis, which may result in bacterial secondary infections by intense scratching as well as anemia, anxiety and embarassment which are increased by children' exclusion from school under "no-nit" policy. From March to July 2011, a cross-sectional study was designed to determine the prevalence and clinical and epidemiological profiles of head lice infestation among 199 (79 males and 120 females) inhabitants of all age groups (0-75 years; ? ± D.S= 21.28 ± 17) of a rural and small town Arenales, from the semiarid region of Falcon state, north-western Venezuela.The diagnosis of head lice infestation was made by clinical naked eye inspection of scalp and hair for the presence of adult lice, nymphal stage, or eggs (nit) by line-toothed head lice comb. Lice was cleared and mounted in Hoyer’s medium for microscopic observation. All individuals were evaluated by physical examinationand a detailed, structured questionnaire. The overall prevalence of head lice infestation was 10.10% (20/199). The prevalence of infestation was significantly higher in girls (90%) than in boys (10%) [Odds Ratio (OR) = 3.04; p = 0.01] and school-aged children (OR= 1.02;p=0,015;) with hair length >3cm (OR = 2,44; p = 0.004) and lissotrichic type (OR = 2.25; p = 0.02), (OR= 2.25; 0.98 - 5.18), however, these were not significantly different among races or hair colours (P > 0.05). 65% of the individuals had only nits with 1 up to 64 per individuals, found between 0.1 and 9 cm from scalp on all anatomical regions of the head, and having school-aged children the higher ectoparasitic loads. Among clinical signs and symptoms, head pruritus (6.53 vs. 12.06%; OR =11.99; p =0.000) and excoriations (1.51% vs. 3.52%; OR =4.34; p = 0.03) showed significantly higher percentages in infested children than in uninfested ones. Other independent risk factors by logistic regression analysis signficantly associated with pediculosis captitis were playing on dust floor (OR = 2.20; p = 0.012), and frequency of hair washing ≥2 /week (OR = 1.01; p = 0.002). These results suggest that pediculosis capitis remains as a common and endemic public health problem in Venezuelan northwestern semiarid region. Thus, education campaigns by health care officials, physicians and teachers, as well as improving standards of living and personal hygiene might significantly reduce pediculosis capitis in those human populations endemically exponed.