Neglected tropical diseases (NTDs) – a diverse group of communicable diseases that prevail in tropical and subtropical conditions in 149 countries – affect more than one billion people and cost developing economies billions of dollars every year. Populations living in poverty, without adequate sanitation and in close contact with infectious vectors and domestic animals and livestock are those worst affected.
Lymphatic filariasis (LF) - Commonly known as elephantiasis, is a painful and profoundly disfiguring disease. It is caused by infection with parasites classified as nematodes (roundworms) of the family Filariodidea that are transmitted through the bites of infected mosquitos. Mosquito-transmitted larvae are deposited on the skin from where they can enter the body. The larvae then migrate to the lymphatic vessels where they develop into adult worms, thus continuing a cycle of transmission.
All ages are affected where filariasis is transmitted. In endemic countries, lymphatic filariasis has a major social and economic impact. Lymphatic filariasis affects over 120 million people in 72 countries throughout the tropics and sub-tropics of Asia, Africa, the Western Pacific, and parts of the Caribbean and South America.
Schistosomiasis - a disease of poverty that leads to chronic ill-health. Infection is acquired when people come into contact with fresh water infested with the larval forms (cercariae) of parasitic blood flukes, known as schistosomes. The microscopic adult worms live in the veins draining the urinary tract and intestines. Most of the eggs they lay are trapped in the tissues and the body’s reaction to them can cause massive damage.
Schistosomiasis affects almost 240 million people worldwide, and more than 700 million people live in endemic areas. The infection is prevalent in tropical and sub-tropical areas, in poor communities without potable water and adequate sanitation.
Onchocerciasis, also known as river blindness, is a disease caused by infection with the parasitic worm Onchocerca volvulus. Filarial worms (O. volvulus) are transmitted from person to person by the repeated bites of infected black flies (Simulium spp.) . These black flies breed in fast-flowing rivers and streams, mostly in remote villages located near fertile land where people rely on agriculture.
NTDs are targeted by the World Health Organization (WHO) through mass drug administration (MDA) programs. MDA is a strategy used to administer NTD medicines to the entire at-risk population of an area, most commonly a district. This strategy takes different forms in different countries, but usually consists of a campaign-style approach to deliver medications to all eligible people in at-risk communities, usually once or twice per year depending on the specific, targeted NTDs.
In the first iteration (Amount of Drug Procured compared to the number of people requiring treatment for a Disease), two data points were used in each of the drug sheets in the JRSM. These were Drugs Procured and the People Requiring Treatment. These values were used to obtain baseline information - see how many drugs were being procured in an area in comparison to how many people they expected to be treated. This ratio was standardized in an effort to easily see whether an area was procuring more drugs per person requiring treatment. The standardization process is stated in the Formulas section. There was one problem with this approach though, and that is verifying the accuracy of the People Requiring Treatment data. Ultimately, the accuracy of these values was left to the the strength of each country's data collection.
In the second iteration (Amount of Drug Procured Compared to the Number of People Treated for a Disease (MDA)), we tried to quantify, to the best of our ability, whether the number of drugs procured was actually necessary. This was accomplished by looking at the MDA data for diseases (from 2017) and also from the ESPEN Portal. The 2017 data are the latest values available, and once the newer data is available, the results will more accurately reflect recent developments. The MDA data is more reliable because it provides the number of people who were actually treated for a specific disease. While each disease may have multiple drugs that could treat it (for example Ivermectin can be used to treat both Lymphatic Filariasis and Onchocerciasis), the number of people treated gives a better estimate as to population treated. With this new data, comparisons to the ratio of the number of drugs being procured per state for a disease and the number of people that were treated with MDA in that state for that disease is between states were made.
The result of the drug comparison is a ratio (Drug Procurement vs Treated) of how many drugs were procured compared to the number of people treated in MDA. Once this calculation was completed, it was then standardized (Standardized Drug Procurement vs Treated). By standardizing it, we are able to see how a country’s ratio compares to the average based on the standard deviation. If the standardized value is positive, then that means they are procuring more drugs per person treated on average. If it is negative, then that means they are procuring less drugs per person treated on average.
Determing if higher or lower than average values are expected can be accomplished by looking at the MDA coverage percentage. If the coverage is low but the standardized value is high, then that means they are procuring drugs but are not able to distribute them properly. If the coverage is high and the standardized value is high, then they are probably procuring more drugs than is necessary. This can be seen in the table below.
| Below average Drug Ratio (DR) | Above average Drug Ratio (DR) | |
|---|---|---|
| Low MDA Coverage | Insufficient procurement | Problematic distribution |
| High MDA Coverage | Satisfactory | Excessive procurement |
This table can be used to draw basic analysis from the MDA coverage value in the tool tip. The problem areas are displayed by highlighting the high and low standardized values as dark areas compared to the rest of the map. Hovering over the area with the mouse will bring up a tooltip that shows the exact ratio. In an ideal scenario, the entire map would be a similar color. Another place to look at this data is the Standardized Procurement Ratio vs MDA Coverage scatter plot in the dashboard. This will allow you to easily identify the problem states as the outliers.
JRSM - (Joint Request for Selected PC Medicines) Excel spreadsheets found in the ESPEN Portal that are filled out by countries to help them quantify how many drugs are needed.
IU MDA Data - CSVs found in the ESPEN Portal that provide information on MDA treatment for a specific disease in a country.
IHME GBD Data - Data obtained from the IHME GBD portal includes YLD, YLL, and DALY statistics for the diseases and countries.
Shape Files - Either found in the Espen portal or from https://data.humdata.org/, depending on which one is more accurate.
Praziquantel (PZQ) is a prescription drug typically used as anti-worm medication. It prevents newly hatched insect larvae (worms) from growing or multiplying in ones body. PZQ is used to treat infections caused by schistosoma worms that enter the body through skin coming in contact with contaminated water.
Ivermectin (IVM) is a presecription drug used to treat infections caused by parasites, threadworms, and roundworms. IVM is used to treat both onchocerciasis and lymphatic filariasis.
Albendazole (ALB) is a prescription drug used for treatment of a variety of worms. Taken orally, this drug is used to treat lymphatic filariasis
The sum of all the drugs procured in each area divided by the sum of all the people requiring treatment in each state, as shown in the JRSM.
The number of drugs procured in each area (from JRSM) divided by the number of people treated in the area (from IU Data).
The number of drugs procured in each area (from JRSM) divided by the number of people treated in the area (from IU Data). This value is then standardized.
σ: The standard deviation
μ: The mean
The number of people treated for a disease (from IU Data) divided by the total number of people who require treatment (from IU Data)
The population of an area (from the JRSM) divided by the YLD rate for the disease (calculated in the IHME Data set)
Normalized DR for each state to be used in the disease measure
Normalized YLD for each state to be used in the disease measure.
Normalized Drug Ratio in each area divided (calculated) by Normalized YLD value (calculated) for the disease in each area
Schistosomiasis: Compares the amount of PZQ procured compared to the population treated for Schisto through MDA (SDP).
Onchocerciasis: Compares the amount of IVM procured compared to the population treated for Oncho through MDA (SDP).
Lymphatic filariasis: Compares the amount of ALB and IVM procured for LF compared to the population treated for LF through MDA (SDP).
Percentage of population who were treated by MDA for each disease compared to population covered.
A scatter of the standardized procurement ratio and the MDA Coverage. The vertical line shows the 0 mark, and the distance from the 0 is how much extra or how much less a country procures. The distance from the 80% is our benchline mark for a good MDA coverage.
Schistosomiasis: Compares the amount of Praziquantel (PZQ) procured for an area and the population requiring treatment in the area (DR).
Onchocerciasis: Compares the amount of Praziquantel(PZQ) procured for an area and the number of people requiring treatment in the area (DR).
Lymphatic filariasis: This map does not exist here. The ALB procured for LF has a considerable amount of missing data in the required treatment field.
Taraba - Low drug procurement rate and low coverage, assess procurement of more drugs
Federal Capital Territory - Procuring a lot of drugs but has a low coverage rate. Possibly need to improve distribution.
Osun - They are procuring a lot more drugs than average compared to the people treated in MDA, but they have low MDA coverage. Need to improve distribution.
Ogun - High number of drugs procured per person treated, but a low MDA coverage percentage. Need to distribute drugs better.
Ogun - High number of drugs procured per person treated, but a low MDA coverage percentage. Need to distribute drugs better.
Oyo - High number of drugs procured per person treated, but a low MDA coverage percentage. Need to distribute drugs better.