Universiti Sains Malaysia virologist Assoc Prof Dr Yahya Mat Arip said it was important to get enough vaccines quickly, even to the remote locations in these states.
People who live in rural areas in these states sometimes face problems traveling to vaccination centres, and registration is a challenge when there is weak mobile or Internet connectivity, he added.
"Factors that might seem trivial such as digital literacy, Internet connection and means of transportation are perhaps barriers to immunisation for many in the six states especially in the outskirts, small districts, and remote areas.
"This vaccine accessibility issue must be addressed if we want to increase vaccination in these states," said Dr Yahya.
The Prime Minister on Aug 29 announced that the six states have been targeted to have at least 50% of their adult populations fully vaccinated by the end of this month, at the very latest.
The move follows an earlier initiative targeting Selangor, Kuala Lumpur and Putrajaya, known as "Operation Surge Capacity".
Operation Surge Capacity, which started on July 17, managed to bend a steep curve of infections that had been raging in the Klang Valley.
The Health Ministry's data also shows a decline in hospital admissions, patients in intensive care units (ICUs).
In contrast, all six of the targeted states are seeing a worrying rise in new cases, hospital admissions, ICU patients, and deaths, amid reports of vaccine shortages in some areas.
Dr Yahya suggested several measures that could help remove the barriers to immunisation in these six states.
These include relying more on vaccines that don't require very low storage temperatures and setting up more community-level vaccination centres.
A "vaccinate first, register later" approach should be also be used, and local village committees and NGOs should be roped in to spread vaccination-related information to people in remote locations.
Universiti Putra Malaysia medical epidemiologist Assoc Prof Dr Malina Osman expressed hope that an initiative similar to Operation Surge Capacity could be done for the six states if there were enough vaccines.
"Walk-in vaccinations including for whole families and collaborations with employers could be considered," she added.
Higher risk profile individuals should also be allowed to pay for vaccinations at general practitioner clinics if supplies are available and can be made more affordable.
"Bring vaccines to the communities instead of asking the people to come to the vaccines," said Dr Sazaly Abu Bakar, senior professor and director of Universiti Malaya's Tropical Infectious Diseases Research and Education Centre, in describing the approach that should be used.
In addition to to ramping up vaccinations, he said authorities should work with community leaders to educate the public on the need to get vaccinated and to seriously practise the new norms.
"In certain circumstances we need to do a real total movement control order and massive screening to 'hunt' for 'cryptic' positives in the communities," he added.