RISK FACTORS CAUSED BY SCORPION STINGS AND ENVENOMATIONS IN THE PROVINCE OF KELÂA DES SRAGHNA (MOROCCO)

The present study aims to elucidate the risk factors involved in deaths caused by scorpion envenomation. A retrospective study was carried out in the province of Kelâa des Sraghna from 2003 to 2004. The hospital charts of scorpion envenomation cases treated in the Essalama Hospital in Kelâa des Sraghna were exhaustively analyzed. Our study contains 31 cases of death among 470 hospitalization cases. Most stings had occurred during the hot period peaking in July and August (54.6%). Moreover, the scorpion stings occurred at night in 60.1% of the cases, between 6:00 pm and 6:00 am. In addition, all age groups were affected by envenomation, with a higher frequency in children aged less than 15 years (68.3%). The envenomation rate (class II + class III) was 70.9%. The statistical analysis of the data shows that being less than 15 years old, having been stung during the night and belonging to class III are risk factors that aggravate vital prognosis of hospitalized patients. Furthermore, clinical severity factors, elicited by relative risk analysis, are cardiovascular, respiratory and neurological vital distresses, with relative risks of 14.84, 11.92 and 48.33, respectively. The results of our study clearly displayed the severity and extent of the scorpion envenomation problem. Thus, great attention must be paid to this region of Morocco by the national health authorities.


INTRODUCTION
Accidents related to scorpion stings constitute a factual problem of public health in several countries in Africa, the Americas and the Middle East, where the mortality caused by this arthropod exceeds those provoked by other venomous animals (16).
In Africa, there are about 30,000 envenomations and 5,000 deaths per year (18). In The studied province presents elevated concern in relation to this problem due to its dry and arid climate, rocky relief and the presence of dangerous scorpion species including Androctonus mauritanicus (Pocock, 1902), Hottentotta franzwerneri gentili (Pallary, 1924) and Buthus malhommei (Vachon, 1949) (Figures 1, 2 and 3).   The current study aimed to determine the factors that can influence the evolution of scorpion envenomation in Kelâa des Sraghna province. In the same manner, we tried to elicit the epidemiological and clinical factors affecting the severity of this pathology in order to improve patient management and to reduce morbidity and mortality caused by these scorpion venoms.

MATERIALS AND METHODS
The province of Kelâa des Sraghna, presenting 10,070 km 2 total area, is 700 meters above sea level (latitude: 32°N; longitude: 7°W). It is part of the Marrakech-Tensift-Al  The charts were filled out in the hospital by the responsible doctor and then were transmitted to the CAPM. The obtained data were analyzed in the Laboratory of Genetics and Biometrics, in the Faculty of Sciences of Kenitra. The studied parameters were: • sting conditions (scorpion species, date, place and time); • demographic characteristics of stung patients (sex and age); • time elapsed between the sting and the arrival at the hospital; • rate of envenomated patients, which corresponds to the ratio between patients of classes II and III to the total patient number.

The statistical analysis concerned:
• intrahospital rate of specific lethality, which refers to the ratio between deaths caused by scorpion stings and the total number of hospitalized cases; • the chi-square (χ²) test, which compares the frequencies observed and expected in each category to verify whether all the categories contain the same proportion of values or if each one contains a proportion of values specified by the user -the differences were considered significant when associated probabilities were less than 5%; • the relative risk (RR) estimate, which measures the association between the presence or absence of a factor and the occurrence of an event. There is a significant difference in the occurrence of some event if the 95% confidence interval for the relative risk ratio does not include 1.

Characteristics of Hospitalized Population in Kelâa des Sraghna Province
The present study showed that most stings occurred during the summer, presenting the two highest frequencies in July (29.40%) and August (25.75%) ( Figure 5). This peak period is mainly explained by the thermophilic nature of scorpions.  The intra-hospital lethality was 6.59%, including 31 deaths among the 470 hospitalization cases.

Influence of Epidemiological and Clinical Factors on Patient Evolution
The results regarding specific lethality for admission classes and age groups are displayed in Table 2. These data show that specific lethality was non-existent in class I patients. Therefore, these patients presented no need for hospitalization. For class II and class III patients, lethality was, respectively, 5.03% and 33.33%.
With regard to age groups, the specific lethality was inversely proportional to patient ages. In fact, it was much higher in children (14.28%, 15.27% and 10.29; respectively, for the age groups 1-4, 5-9 and 10-14 years) in comparison with patients who were aged 15 years or more (0.9%). We should note that 96.8% of the deaths happened in children.     Table 4). The other systemic signs were not significantly related to death, as shown by the chi-square test and the confidence interval of the relative risk. The stings in Kelâa des Sraghna are most frequent in July and August, which concurs with the results found in other places throughout the world. Indeed, the periods that present predominance of scorpion stings were reported in different countries as follows: Mexico, from April to July (11); Tunisia, from July to September, presenting the peak in August (7); however, in Brazil stings occur uniformly throughout the year, with a slight increase in August (10). These small temporal variations may be due to environmental conditions (17). The limitation of these events to the summer is explained by the thermophilic nature of the scorpion, which is widely supported by several studies (1,13,19,20,24). Additionally, the stings occurred particularly between 6:00 pm and 6:00 am (60.1% of the studied cases) because of the nocturnal activity of this arachnid (2,4,6,8,14,21).
In the present study, children younger than 15 years old presented a high mortality rate. This child vulnerability to scorpion stings was also reported by by Islami (9)  The present findings clearly displayed the severity and the extent of the scorpion envenomation problem. Thus, great attention must be paid to this region by the Moroccan health authorities. In fact, if we consider that this hospital is the only resort for stung patients of Kelâa des Sraghna and that the period of high scorpion activity corresponds to the typical schools vacation period (July and August), it would be necessary to reinforce the medical staff and to improve intensive care equipment to obtain a better management of this pathology.