Lightning Injury is a disaster in Bangladesh? - Exploring its magnitude and public health needs

Quantitative method

A large cross-sectional study was conducted during January to December 2003 in twelve randomly selected districts in Bangladesh and also in Dhaka Metropolitan City. Multi-stage cluster sampling was employed to select 171,366 households (88,380 in rural areas and 45,183 in urban areas in the twelve districts, and 37,803 in Dhaka Metropolitan City). The current study is part of this larger study. Each district consists of several upazilas (subdistricts). From each district, one upazila was chosen. The upazilas contain smaller units called “union”. A union is the lowest administrative unit, with a population of approximately 20,000. In this study, two unions from each of the upazilas were selected. Similarly, in urban settings, the mohalla is the lowest unit of the City Corporation. Systemic random sampling was performed of a certain number of households in selected mohallas.

Prior to data collection, 48 trained interviewers had visited the selected households and explained the study objectives and ethical issues. They then conducted the questionnaire survey. As well, 819,429 people of all age groups from 171,336 households in those twelve districts were selected and interviewed using face-to-face interviews.

Persons who were injured by lightning and received treatment or who were unable to perform their usual activities for at least 3 days because of lightning injury were enrolled in the study. We also interviewed the next of kin of people who had died from lightning injuries. About 2.7% of households could not be interviewed because of unavailability of respondents in the households. A total of 166,766 households were included in the study. The methodology has been described elsewhere^8,9.

Review of the newspapers and electronic media subjected to content analysis

Daily national popular Bangladeshi and English-language electronic newspapers were searched for reports on lightning injuries. Two Bengali and three English-language national newspapers which are widely read in Bangladesh were selected. In addition, we searched international online news sites. Three international English-language newspapers and three purposively selected international online news sites were also included in the search.

As previously mentioned, a high number of lightning events have been reported in Bangladesh for the period 13–15 May 2016. Therefore, we reviewed newspapers to find information on these events. Two researchers collected the relevant information from the selected sources. The next morning, two different researchers sat together and read the news headlines to select relevant articles and eliminate duplicate news. They further read all collected news and then made a further selection pertaining to the study aims. The researchers, who were bilingual, also translated the Bengali news into English.

Only articles relevant to the aims of this study have been included in this study. Each newspaper article constitutes a unit of analysis. Two qualitative researchers conducted content analysis. To determine the overall content and framing of the article, the researchers read, re-read and annotated the news articles by attaching key words to segments of text¹⁰.

Statistical analysis of quantitative data

Standard descriptive statistics using means, standard deviation (SD) and proportions were used to analyse the characteristics of lightning victims. The gender, age, and place of residence of cases of lightning injuries were determined. Cases were categorized into eight age groups. The yearly incidence of lightning injuries was estimated from the occurrence of lightning morbidity in 6 months, multiplied by 2. The reason was that data were collected with a recall period of 6 months. Rates were calculated and 95% confidence intervals (CIs) computed. We estimated the relative risks (RRs) in relation to different age groups, place of residence, and gender. We used cross-tables and EPI-Info 6 software.

Ethical issues

The current study formed part of a larger study titled “Bangladesh Health and Injury Survey (BHIS)”. The study has received ethics approval from the Ethics Committee of the Institute of Child and Mother Health, Dhaka. Participants were informed about the benefits and objectives of the study. Written consent was obtained from each head of household before proceeding with the interviews. The participants were told that they had the right to withdraw from the study at any time and the study objective was explained to them. Data collectors were trained in ethical issues.

Media news was publicly available. Information from media was anonymously presented without any direct quotation from the media reports. Also the study had not used any personal identification and information related to media reports.

Quantitative findings

Incidence. A total of 163 people with lightning injuries were identified, 98 males (60.12%) and 65 females (39.8%). Of them, 160 (98.15%) had suffered non-fatal injury and three (1.84%) had died. The annual death rate was 3.661 (95% CI 0.9313–9.964) per 1000 people. The overall incidence of lightning injury was 19.89 per 100,000 people. Males were more vulnerable, with a 1.46 times higher risk of being hit by lightning compared with females (RR 1.46, 95% CI 1.06–1.99). The mean age of the victims was 26.2 (SD±21.83) years (range 2–75 years). Altogether 84 (51.5%) of those struck by lightning were children. The highest incidence of injuries was found in the age group of 50 and above (Figure 1).

Figure 1. Annual incidence of lightning injuries by age group.

Magnitude of the injury. The majority of victims were of poor socioeconomic status, 86.7% (n=139), with a monthly income of <US$100. Students (31.2%), agricultural workers (17.9%) and housewives (14.5%) were the main victims of lightning injury. Among the victims, 90.80% (n=148) were from rural areas and 9.20% (n=15) from urban areas. People from rural areas were more vulnerable, with an 8.73 times increased risk compared with urban populations (RR 8.73; 95% CI 13–14.86).

About 36% (n=59) of the injuries took place between 6 am and 12 pm, while 43.2% (n=71) occurred between 12 noon and 6 pm, and 18% (n=29) from 6 pm to midnight. A total of 31.7% of victims were outside at work when lightning struck; 24.6% were travelling when they were hit by lightning. Home courtyards were the most common places (65.1%) for lightning strikes, followed by roads and footpaths (26%).

The leg was the most common site of injury, with an incidence of 63.5% (n=97), followed by hand injury in 17.4% of cases (n=27) and abdomen injury in 10.5% (n=16). Among the casualties, 95% (n=155) sought treatment from different level health care providers, with the majority of people (n=134) seeking treatment from the village doctor or traditional healer (83.1%). Only 7.3% (n=8) received treatment at a health facility. Among the injured, 41.8% (n=68) were unable to perform regular activities for 1–6 days while 19.1% (n=31) were unable to do so for ≥1 week. Only 1% (n=2) of the injured reported the incident to the police (Table 2).

Findings from media reports

Bangladesh has had a high incidence of preventable deaths from lightning for decades. Data on the period 2005–2016 showed that the highest number of deaths in a single day was in May 2016, when lightning killed 81 people in 26 districts, mostly in the rural north and central Bangladesh^11–13. By comparison, lightning deaths between 2005 and 2008 totalled 41. Over the next few years, the number of deaths progressively increased. The English-language Bangladeshi newspaper Daily Star reports that from 2010 to 2016 a total of 645 people died in thunderstorms¹⁴. Another source, the Foundation for Disaster Forum in Bangladesh, reports 1390 deaths due to lightning for the period 2010–2015¹⁵ (Figure 2). Other newspapers have reported that an average of 300 people die every year in Bangladesh due to lightning; however, this is underreporting^11,16,17.

Figure 2. Magnitude of lightning injury from 2010 to 2015, according to the Foundation for Disaster Forum.

According to the newspaper reports, the youngest person who died from lightning was 13 years old, and the oldest lightning victim was 70 years. In most cases, lightning occurred outdoors in a rural area while the person was performing daily household work or other usual activities. One newspaper reported that 51% of the fatalities were farmers who were working in the fields.

According to the National Geographic, lightning storms in Bangladesh occur mostly in May and in the afternoon, when the temperature is high. The fact that the country is densely populated contributes to the high incidence of human lightning strikes. Other sources also mentioned an increase in deforestation, and the felling of tall trees, as a contributing factor. In addition, use of metal objects such as mobiles or structures such as cell phone towers or electrical power distribution towers can result in lightning deaths. It was also mentioned that in rural areas, taller trees usually attract lightning flashes. Internationally, scientists have warned that an increase in lightning storms may happen as part of climate change and global warming. Global warming is causing more water evaporation, increasing cloud formation, the amount of rainfall and the potential for lightning storms^18–20.

After the fatal lightning injury event in May 2016, the Bangladesh government declared lightning a disaster, adding lightning injuries to the country’s list of official types of natural disasters, which includes droughts, floods, cyclones, storm surges and riverbank erosion, and earthquakes^20,21. In 2016 the government pledged to compensate lightning strike victims and/or their families^12,22.