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By Dagna Constenla, Gatien de Broucker, Jorge Martin del Campo and Alexandra Greenberg, IVAC at Johns Hopkins University

This article was originally published on the Dengue Vaccine Initiative's blog and is cross-posted here with permission. IVAC is a member of the Dengue Vaccine Initiative (DVI). 

The successful introduction of a vaccine in affected countries depends heavily on issues such as supply constraints, potential demand, and the impact of policy decisions on future demand and supply. Strategic demand forecasts (SDFs) play a central role in enabling vaccine suppliers, donors, and country-level stakeholders to make informed decisions about vaccine supply, financing, and adoption. In recent years, Accelerated Development and Introduction Plans (ADIPs) have used strategic demand forecasts to adjust market forces for the purpose of accelerating access to new vaccines in countries where they are needed the most.

Our team at the International Vaccine Access Center at Johns Hopkins University has developed several models to estimate the potential demand of dengue vaccine and the costs associated with dengue introduction programs, enabling vaccine suppliers, donors, and country-level stakeholders to make informed decisions about vaccine supply, financing, and adoption. These models have been developed with specific price and coverage assumptions for a variety of target ages and regions.

For the next phase of our project, we will quantify the potential demand for dengue vaccines in Latin America, specifically Mexico, Colombia, Honduras, Paraguay, El Salvador and Peru, taking into account the different scenarios envisioned by each country. Using advanced economic modeling, we aim to determine which factors would drive dengue vaccine demand in these countries.

Building off of our team’s current work on a similar model in Brazil, our team will develop SDF models in collaboration with the Ministries of Health in Mexico, Colombia, Honduras, Paraguay, El Salvador and Peru. While we already have access to relevant information in some of the countries in the region, this collaborative work is essential to ensure that the outputs of the model are relevant and integrated in the decision-making process for each country of interest.

Approaching six different countries at the same time brings many challenges in forecasting the potential demand of the vaccine. Each country has unique characteristics that impact the way vaccine introduction decisions are made. Differing geographical specificities, population demographics, health systems and political infrastructure within countries are good examples.

While strategic demand forecasts can be powerful communication tools, they have certain limitations. SDF depends on the availability of vital pieces of information from stakeholders, namely in-country policy makers, industry, and global donors. Getting information from one stakeholder can be hard without the ability to rely on credible information from other relevant players. All stakeholders must participate with equal commitment towards providing timely and accurate data for the results of strategic demand forecasts to be valid. The lack of reliable information can also make it difficult to verify or test key assumptions made by disease modelers.

In addition to the potential absence of consistent and reliable information, it can be challenging to generalize across developing countries. Significant differences in low- and middle-income countries can make operating conditions vastly divergent on the ground, thereby making broad-based assumptions and generalizations ineffective. Economic and political conditions – such as the unequal distribution of resources and infrastructure, limited budgets, inadequate healthcare policies, and divergent political priorities – can vary substantially between countries, even within the same sub-region.

Lastly, unequal financial commitment from international and local donors makes it difficult to determine the price funders would be willing and able to pay for a vaccine. This is an especially crucial piece of information for low-income countries, which would be unable to introduce a new vaccine without significant support from outside funders. Without this vital information it is challenging to estimate the potential demand for a vaccine in any given market.

So far we are having fruitful discussions with highly positioned local stakeholders in each country including program heads, government officials and representatives at the national and state levels. Their response has surpassed our expectations: they are themselves working to engage new key actors in this discussion. Stakeholders are driven and committed to understanding this disease and to ensuring that a vaccine is introduced in the most efficient and beneficial way for every country.

This research will be critical for laying the groundwork so that countries in the Americas can establish a viable vaccine introduction plan, which can be immediately implemented following the introduction of a dengue vaccine.

By Rebecca Van Roy, Communications Officer, Vaccine Advocacy and Education at Sabin Vaccine Institute

This article was originally published on the Dengue Vaccine Initiative's blog and is cross-posted here with permission. IVAC is a member of the Dengue Vaccine Initiative. (DVI) 

Earlier this year, DVI convened the Americas Dengue Prevention Board along with scientists, global health experts, mathematical modelers and representatives of dengue vaccine manufacturers to discuss updates in dengue vaccines and vaccine introduction. Held in Bogota at the Colombian National Institute of Health (Institituto Nacional de Salud – INS), the meeting was instrumental given the new available clinical trial data, particularly the results of the first Phase 3 trials ever completed for a dengue vaccine candidate. These results demonstrated that a safe and effective dengue vaccine is feasible

A mosquito that costs over $2 billion

Dengue, caused by a small mosquito with black and white striped legs, is the most widespread vector-borne disease in the Americas. In 2013, cases and deaths nearly doubled those of previous years in the region. The southern cone reported the highest incidence rate of cases, but the Andean region reported the highest number of severe cases. The burden of dengue in the Americas has been estimated at more than $2 billion dollars, from hospitalization costs to loss of productivity, representing a significant threat to the wellbeing of the region.

A safe and effective vaccine can help reduce this threat. While the decision to introduce a dengue vaccine can only be driven at the country level, such decisions must be based on sound evidence. DVI Dengue Prevention Board Meetings seek to share and update existing dengue knowledge and identify gaps to ensure countries have scientific, objective data to make informed public health decisions proactively, before a vaccine becomes available.

An open forum to share dengue knowledge –-and its gaps

With this objective in mind, the meeting offered an open forum where participants revisited the minimum requirements for successfully launching a dengue vaccination program among other crucial dengue topics.

On the first day, they reviewed the status of dengue vaccine development with representatives of the manufacturers of the five vaccines in clinical trial (Butantan/NIH, GSK/Fiocruz/Walter Reed, Merck, Sanofi Pasteur and Takeda). They also discussed the applications of mathematical modeling for predicting the impacts of dengue vaccination.

On the second day, country representatives presented the current dengue situation in their homeland and perspectives on dengue vaccine introduction and use.

Finally, the meeting broke into groups to assess considerations for vaccine introduction. The Board then met separately to draw conclusions. The meeting ended with the closing remarks of the Colombian Ministry of Health, who highlighted the spread of dengue and the urgent need to stop it. 

Board Conclusions

The Board noted the critical importance of linked disease surveillance and vaccination registries to monitor coverage and vaccine effectiveness, as well as monitoring for vaccine safety. They also urged the standardization of age groups and case definitions of dengue disease across countries in the region to enable comparisons. They called for further analyses to understand how a limited supply of vaccine might best be utilized in the first year(s) of vaccine introduction. They affirmed the importance of the Pan-American Health Organization (PAHO) for supporting vaccine introductions, particularly through activities such as issuing recommendations for laboratory-based disease surveillance in the region, with an aim of standardizing the diagnostic tests.

The table below summarizes these conclusions. For more detail we encourage you to read the full report here: “Development of Dengue Vaccines: A Review of the Status and Future Considerations.


About Dengue Prevention Boards

In 2007, PDVI (Pediatric Dengue Vaccine Initiative—DVI’s precursor) established two regional Dengue Prevention Boards (DPBs) — one for Asia and one for the Americas. Members of the boards include medical and public health experts, opinion leaders and policy makers from countries in their respective regions. They meet once a year to advise on dengue surveillance, diagnostics, vaccine introduction and communications.

All reports on DPB meetings are published in the DVI website to inform dengue and global health stakeholders.

By Lois Privor-Dumm and Huma Khawar.

This article was originally published on Vaccineswork and is cross-posted here with permission.


Photo: UNICEF/PAK 2015/Asad Zaidi

In Nigeria and around the world, citizens, governments, doctors, and parents are fighting polio – and they’re winning. After nearly 30 years of polio eradication efforts, the end is in sight. In 1988, the year the World Health Assembly (WHA) resolved to eradicate polio, there were an estimated 350,000 polio cases globally; last year there were only 359, and this year cases so far are down by 75%.Misbau Lawan Didi leads a club he wants to eliminate. As president of the Polio Survivors Association, he is committed to not only end polio in Nigeria but to eradicate it from the planet. “We are determined,” he says, “to ensure that our members are no more.”

Polio has eluded us for decades. There have been plenty of starts and stops and lots of excitement about the polio eradication effort.

So what makes this time different?

Communities around the world are mobilizing, and momentum is building. Last month, one of the remaining three endemic countries, Nigeria, passed the one year mark without a single case of wild poliovirus. Once the final samples are tested and cleared, the World Health Organization should even be able to declare Nigeria a non-endemic country. Many thought it wouldn’t be done.  

Now, Pakistan is embarking on one important step in its fight against polio and implementing the endgame strategy with introduction of the inactivated polio vaccine (IPV) across the country. It will take determination and sustained effort to ensure that it can be done – and with a decentralized health system, years of war, and continued threats against health workers, it will be no easy feat.

Step by step, progress is being made. We are on the brink of an unprecedented accomplishment. Yet, public health experts warn “the last mile” will be the hardest. Ending transmission of the virus in every country will take a focused effort and the use of every available tool against the disease. The Polio Eradication and Endgame Strategic Plan was developed to provide countries with a roadmap to help navigate this challenge. The plan calls on countries to make three important changes to their immunization efforts: 1) to introduce one dose of (IPV) into routine immunization schedules, 2) to strengthen routine immunization, and 3) to eventually withdraw oral polio vaccine (OPV).

The first phase of this plan, the introduction of IPV, is well underway. While there was initial concern over an accelerated timeline, communities and governments around the world have risen to the challenge. The introduction of IPV will be one of the fastest rollouts in history. Out of 126 oral polio vaccine (OPV) only using countries, 30 have now introduced. Today, on August 20th, Pakistan launches its nationwide rollout, which is no small feat. The significance of this rollout is monumental.  


Photo: UNICEF/PAK 2015/Waseem Niaz

Introducing a new vaccine involves hundreds of technical and logistic details. There are budget considerations, procurement, storage and transport of vaccines, training of health workers, and communication with parents. Countries need to assess their systems and strengthen necessary components. In Nigeria, for example, communicating with the public was particularly important as skepticism about the polio vaccine halted past efforts. When Nigeria introduced the new polio vaccine in February of this year, community and religious leaders were active in the outreach to parents. In markets and in mosques, the public was told about the importance of immunization and using the IPV vaccine in the battle against polio. In February, when Nigeria became the first polio endemic country to introduce the vaccine, it was widely accepted by parents.

We are down to the last three polio endemic countries – Nigeria, Pakistan and Afghanistan – and now there is even greater hope.  Last year, there were no new members of Nigeria’s Polio Survivors Association as the country did not have any cases of the disease. Work in Nigeria is far from over, but the effort is paying off: two more years without a reported case and Nigeria can be certified as polio free.

The same can be true in Pakistan and the other countries where communities are hard at work to protect their children and eradicate this virus. This time it really can be different. Pakistan, is your time now?

Lois Privor-Dumm is the Director of Policy Advocacy & Communication at IVAC at the Johns Hopkins Bloomberg School of Public Health. Huma Khawar is a freelance journalist and consultant based in Islamabad who works with stakeholders on the ground in Pakistan to advocate for new vaccines through the Vaccine Implementation Technical Advisory Consortium (VITAC), a project of the Gavi Alliance.

With the help of a long list of partners and supporters, IVAC has developed a portfolio of advocacy materials supporting IPV introduction, which can be found here. Inquiries can be directed to Lois Privor-Dumm at

By Dr. Anne von Gottberg, Respiratory and Meningeal Pathogens Research Unit, National Institute for Communicable Diseases

This article was originally published on and is cross-posted here with permission.

If you had looked at South Africa’s invasive pneumococcal disease (IPD) surveillance data before 2002, you would have never guessed that one day that data would land on the pages of the New England Journal of Medicine

Even I thought such a feat was impossible. Surveillance for IPD was passive and patchy – certainly not the kind of data you could use to examine trends or measure impact.  In 2002, experts in pneumonia and respiratory disease suggested that we completely revamp the system: start measuring antimicrobial resistance and serotypes, obtain clinical data from cases to explore risk factors for resistance.  Although this was long before the pneumococcal conjugate vaccine (PCV) was introduced, we knew any investments we made in the surveillance system now would pay huge dividends later, and possibly allow us to measure the impact of PCV introduction.

Noluthando Duma works in the lab

An example of disease surveillance activities. Here, Noluthando Duma works in the lab. Photo: NICD.

Revamping a national surveillance system was not an easy task.  Our institute managed the process - from employing surveillance staff throughout the country to collecting data - and we had many, many challenges.  This project seemed so unusual, so impossible, that it was difficult to convince anyone to join us.  We would interview surveillance officers at remote regional sites who wondered how they could report to a central office in Johannesburg, given that they had never even been there; they couldn’t imagine how such a big, unwieldy national program could ever work. We would answer their questions with what I hoped sounded like confidence, but the truth was that we were figuring out the answers as we went along.

Despite these human resource challenges, we charged ahead, but it was a slow-and-steady race.  At our national surveillance officer and principle investigator meetings, we had to bring together key stakeholders to discuss the surveillance network.  We had to get buy-in on the methods, the case definitions, the flow of data, and sharing of information, and then we had to hire staff to operationalize our ambitious plans. Many new hires had never been on an airplane before, and some had never seen the ocean – the surveillance network really made South Africa smaller, bringing people together in the “new South Africa” in ways that I could not have predicted. So we anxiously booked window seats, made time for quick excursions to the beach, and hoped for the best. And although we had our fair share of hiccups along the way, our small team continued to grow, the years passed, and we kept on finding ways to silence the naysayers!

Meanwhile, things did not stay still around us.  The South African government suddenly found the political will to tackle the HIV/AIDS epidemic, and with a tremendous effort, the government and civil society rapidly improved care of HIV-infected pregnant women, HIV-infected children, and adults in general.  With these sudden improvements in healthcare, IPD also changed, making it more difficult to attribute any declines to the vaccine, even with the new surveillance system.  But through a series of discussions with local and international colleagues and friends, countless conference calls, and careful review of the data, it finally became possible to tell the story that was in the data, collected for so many years by our dedicated surveillance teams.


Colleague Kedibone Ndlangisa conducting lab work. Photo: NICD

Last week, as experts and decision makers gathered in Kenya to discuss the results of various PCV impact studies from across Africa – all showing significant reductions in pneumococcal disease after the introduction of the vaccine – I was reminded of how far we had come on our journey and the many lessons learned on our path. 

By maintaining our slow-and-steady approach remembering to “ask a friend” when we were stumped, and above all continuing to plow on in the face of challenges, we were able to turn data that at first glance may have looked like a mess into a meaningful and robust assessment of the impact of PCV. 

This study is part of the the Vaccine Implementation Technical Assistance Consortium (VITAC) - a collaboration of PATHCDC, and IVAC - supports the achievement of the mission to save lives, prevent disease, and promote health through timely and equitable access to new and underused vaccines. VITAC is focused on accelerating the introduction and sustained use of vaccines by creating the evidence base, advocating for evidence-driven decision making, and establishing a platform for countries to assess the resources needed for sustained and optimal use of vaccines.

This article was originally published on Global Health Now and is cross-posted here with permission.

By: Dr. Mathuram Santosham

A healthy child in Uttar Pradesh, India, 2010 © Gates Foundation

World Immunization Week provides a moment to reflect on the tremendous progress in reducing one of the world’s leading killers of children—diarrhea.

While oral rehydration solution has significantly reduced diarrheal disease mortality since its adoption in 1978, diarrhea continues to be a major cause of childhood illness and death globally. Rotavirus, the most common cause of severe diarrhea, is responsible for approximately 40% of all diarrhea hospitalizations and hundreds of thousands of deaths in children under 5.

Rotavirus vaccines offer the best protection for children and are an essential part of comprehensive diarrhea control. While the WHO recommends that all countries introduce rotavirus vaccines, only 77 have done so, 34 of which are Gavi-eligible countries where many of the deaths occur. Unfortunately, some of the most vulnerable children and communities do not have access to the vaccine.

In particular, Asia has lagged in introducing rotavirus vaccines, even though it accounts for more than 40% of global rotavirus deaths. To date, no country in the region has introduced the vaccine into its national immunization program.

While dramatic reductions in deaths from childhood diarrheal disease have been achieved in Bangladesh, there are still more than 2.4 million rotavirus cases each year. It causes 2 out of every 3 diarrhea-related hospitalizations among children under 5. There are also serious economic consequences. One episode of rotavirus costs the average Bangladeshi family about USD $80 in direct hospital costs, a significant portion of average monthly income.

In neighboring India, where rotavirus is equally ubiquitous, the disease poses a significant financial burden to families and the country’s economy. Studies have shown that a hospitalization for rotavirus could potentially push a family into poverty or keep them there. Depending on the level of care, the total cost of a rotavirus hospitalization could range anywhere from nearly $32 to more than $135, equal to up to 2 months of income for an average Indian family. Rotavirus also burdens the healthcare system with the high cost of hospitalizations and outpatient visits. One study estimated that hospitalizations and outpatient visits cost India approximately $78 million and $86 million each year, respectively—each more than the estimated $72 million it would cost to fund a rotavirus immunization program.

For fast-growing countries like India and Bangladesh, tackling rotavirus—which cheats children and the nation of productivity, well-being and development—should be a priority. However, the available and effective rotavirus vaccines are not yet available in the national immunization programs of either country. 

Many of my scientific colleagues in Bangladesh are making a good case to their leaders for national introduction of rotavirus vaccines. And, I’m inspired by the strides being made in India. Last July, Prime Minister Narendra Modi announced that rotavirus will be included in the Universal Immunization Programme; and just last month, the first India-made rotavirus vaccine, ROTAVAC, was launched. Now is the time to get to the finish line—the cost of delaying access to rotavirus vaccines continues to mount. Together we can close this immunization gap and virtually eliminate rotavirus.

Dr. Mathuram Santosham is the Director of the Center for American Indian Health, Chair of the ROTA Council, and Senior Advisor at the International Vaccine Access Center at Johns Hopkins Bloomberg School of Public Health. Dr. Santosham and his colleagues won an Honorable Mention in GHN's Untold Global Health Stories Contest for their submission of rotavirus in Bangladesh and India. GHN will feature one Honorable Mention story per month from now until the next contest in early 2016.