Comparing influenza positivity rates by real-time rt-pcr, elisa and viral culture methods in Cote d'Ivoire, West Africa, in 2009

Detection of circulating influenza strains is a key public health concern especially in limited-resource settings where diagnosis capabilities remain a challenge. As part of multi-site surveillance in Cote d'Ivoire during the 2009 influenza A(H1N1) pandemic; we had the opportunity to test respiratory specimens collected from patients with acute respiratory illness (ARI). We analyzed and compared the percentage of specimens testing positive using three laboratory methods (rtRT-PCR; ELISA; viral culture). From January to October 2009; 1;356 respiratory specimens were collected from patients with acute respiratory illness and shipped at the WHO NIC (Institut Pasteur) Cote d'Ivoire; and 453 (33) tested positive for influenza by one or more laboratory methods. The proportion of positive influenza tests did not differ by the sex or age of the patient or presenting symptoms; but did differ depending on the timing and site of specimen collection. Of the 453 positive specimens; 424 (93.6) were detected by PCR; 199 (43.9) by ELISA and 40 (8.8) by viral culture. While seasonal influenza A(H1N1) virus strains were prominent; only four 2009 pandemic influenza A(H1N1) cases were detected. Use of molecular biology method (rtRT-PCR) increased sensitivity and diagnosis capabilities. Among all three methods used; rRT-PCR was the most sensitive and rapid method. More capacity building is still required for viral culture. Need to collect denominator data in order to have an accurate estimate of the burden of influenza. There was delayed introduction of pandemic influenza A(H1N1)2009 in Cote d'Ivoire

The crystalloid vs colloid controversy in the era os hypertonic/hyperoncotic resuscitations: is the debate over?

The crystalloid vs. colloid controversy has been further complicated by the inclusion of hypertonic levels of sodium chloride (HTS) in both types of regimens. In this paper the recent literature on the controversy is reviewed. Colloids raise the intravascular colloid osmotic pressure and increase the fluid retention in the vessels. Crystalloids however, distribute into the interstitial and intravascular spaces at a ratio of approximately 3 to 1. It is therefore necessary to infuse a large volume of crystalloids in order to complete resuscitation. The advantage of colloids over isotonic crystalloids focuses primarily on the incidence of pulmonary edema. In an analysis of clinical trials, however, colloids were not proven to be superior to crystalloids. The use of HTS decreases the amount of crystalloid required for resuscitation. Pulmonary and systemic vasodilation, an increase in cardiac output and stroke volume, decreased intracranial pressure and an enhanced immunologic response have been noted experimentally, and the clinical evidence seems to corroborate these findings. HTS with dextran (HSD) has been used in an attempt to combine the rapid cellular fluid shift of hypertonicity with the vascular fluid shift of colloids. The experimental evidence is compelling. Whereas HTS has proven itself to be a superior resuscitation regimen, HSD has not yet warranted in a clinical setting the optimism which its experimental studies seem to indicate.